Windows does not not errors

Similar Questions

• Error one of the UBS damage connected to this computer has malfunctioned and windows does not recognize it

  Original title: Canon MF 4500 printer inkjet

  My computer tells me that 'one of UBS damage connected to this computer has malfunctioned and windows does not recognize"it could the cable, as the printer (canon MF 4500) does not work.

  Hello

  1. what operating system is installed on your computer?

  2. when exactly you receive this error?

  3. all USB devices work properly on your computer?

  4. have you made changes on the computer before this problem?

  Method 1:

  You can try running the fix - it from the following link.

  Hardware devices do not work or are not detected in Windows

  http://support.Microsoft.com/mats/hardware_device_problems/

  Method 2:

  You can try to uninstall and reinstall the USB controller. Follow the steps.

  (a) click Start and then click Control Panel.

  (b) click System and Maintenance, click System, and then click Device Manager.

  Note: If Control Panel is in Classic view, double-click System and then click on Device Manager.

  If you are prompted for an administrator password or a confirmation, type the password, or click on allow.

  (c) in Device Manager, double-click to expand the "USB Bus controllers", right click on the controller host, click "Uninstall" and click "OK".

  Check that if at all, there is an exclamation point on the pilot, it suggests problems with the installed driver.

  (d) repeat step 2 to uninstall all items under 'USB Bus controllers'.

  Then, restart your computer and Windows will automatically reinstall all USB controllers.

  It will be useful.

• Windows does not update with error code 8024402C

  Windows does not update with error code 8024402C

  Quote your full version of Windows (for example, WinXP SP3;) Windows XP 64 - bit SP2; Vista SP1; Vista 64 - bit SP2; Win7; Win7 64 bit) when you post in a forum or a newsgroup. Please do it in your next reply.

  What application or antivirus security suite is installed and your current subscription?  What anti-spyware (other than Defender) applications?  What third-party firewall (if applicable)?

  A (another) Norton or McAfee application has already been installed on the computer (for example, a free trial version which is preinstalled when you bought it)?

  0x8024402C error code when you try to install updates on Web Windows Update or Microsoft Update sites:
  http://support.Microsoft.com/kb/900936

  ~ Robear Dyer (PA Bear) ~ MS MVP (that is to say, mail, security, Windows & Update Services) since 2002 ~ WARNING: MS MVPs represent or work for Microsoft

• I am running Xp SP2 Windows does not update anything more and gives me [error number: 0x8024400A] Why can't update Windows again?

  I am running Xp Sp2 and about a month, there are, I tried updating to SP3 (new) and it sends my computer fits in. It keeps just reboot and reboot (SP3 has always done this has my computer since its release). I had to do a cover of the plant to return to the place where he could start normally but now Windows does not update anything. I go to Windows Update, it goes through the motions of checking to see if everything is legitimate, click the express button and gives me "the website has encountered a problem and cannot display the page you are trying to view. The options provided below may help you solve the problem. [Error number: 0x8024400A]   After going through the links provided and find no solution the last link sent me here. So why can't update Windows?

  Hi kriplurr,

  Thank you for keeping us posted about the State of the question.
  I'm glad you are able to run the updates.
   
  You can download the Windows Installer under the following link and check.
  Windows Installer 3.1 v2 (3.1.4000.2435) is available
  seehttp://support.Microsoft.com/kb/893803
   
  Or you can download it directly at the following link.
  http://www.Microsoft.com/en-US/Download/details.aspx?ID=25
  (a) click on the above link.
  (b) click Download next to WindowsInstaller-KB893803-v2 - x 86-.exe
  (c) install and check.
   
  Hope this information helps.

• Error code 0 xC0000001 on Asus Vivo tab Rt with RT Windows does not start

  Error code 0 xC0000001 on Asus Vivo tab Rt with RT Windows does not start

  Hi guys,.

  I hope you can help, I bought an Asus Vivo tab RT with month windows RT 13 there, I used it only for the first two weeks after I bought and then travel. I went back to find he does not start and going to a blue with 0 xC0000001 error screen after several attempts of the operating system on your PC could not start, so it needs to be repaired.

  It is now one month out of warranty and ASUS refuse to provide support for me, I used the recovery media to reset the Tablet, but still he starts to this message.

  I'm not sure what I can do, I'm totally stuck. Can anyone offer some advice on what I can try? anything via the command prompt?

  At this point I have an expensive paper weight.

  Thanks in advance

  Joel

  Hello Joel,
   
  Usually, the error code 0 xC0000001 indicates that winload.exe in C:\Windows\System32\Boot could not be found or is corrupted. This could be the result of a corrupted download, before the creation of the operating system.

  Since Windows RT came pre-installed and require installation media to retrieve the device, you may need to contact Asus support for assistance.

  http://support.ASUS.com/ServiceHome.aspx?SLanguage=en

  I'm really sorry not to be useful in this regard.

  Please do not hesitate to contact us for any further assistance on Windows.

• Make a right click on the folder responds slowly and sometimes get an error "windows does not.

  original title: pc maintenance

  Make a right click on the folder responds slowly and sometimes get an error "windows does not.

  Make a right click on the folder responds slowly and sometimes get an error "windows does not.

  This could be due to so many things. Malware, applications in resources, solutions anti-virus, hard drives damaged, damaged file system, processor ram capacity limitation...

  can't tell what your problem exactly, you can use the reliability monitor, event viewer to discover additional problems...

  What does it mean when a program is not responding? http://Windows.Microsoft.com/en-us/Windows-Vista/what-does-it-mean-when-a-program-is-not-responding

• Error - "one of the usb devices attached to this computer has malfunctioned and windows does not recognize it

  Original title: USB device not recognized / dysfunction

  "Unrecognized USB device".
  One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it. Help for this problem, click this message. »

  This is what I get AFTER that I had to reinstall windows XP because a virus has attacked my computer a little before avg and Microsoft security essentials picked it up and destroyed... I have reinstalled twice... then I changed discs since I have two... well, I get this message from my 2 external Seagate Freeagent and my Phillips mp3 go gear aria... player these devices work on the laptop from my friend and she is under vista. It seems that since then they have worked on my computer before they would always run. My mouse and my cam work fine and my Canon printer gets thus detected... a few readers who have the space that is made... Ive looked everywhere for a solution... even upgraded windows media 11 and is player went to service pack 3. restarted several times... tried dPower Management tab and tried to

  Open recognition of the USB device by using Device Manager.

  .. I am at a loss: P please help thanks!

  isable the power management of the USB hub and I couldn't find the

  Hi LadyDefi,

  You can try to uninstall and reinstall the USB controllers and check:

  To remove and reinstall all USB controllers, follow these steps:

  a. Click Start, click Run, type sysdm.cpl in the Open box and then click OK.

  b. click on the Hardware tab.

  c. click the Device Manager button.

  d. expand Bus USB controllers.

  e. right click on each device under the Bus USB controllers node and then click on uninstall to remove them one at a time.

  f. restart the computer and reinstall the USB controllers.

  g. plug in the removable USB storage device and test to make sure that the problem is solved

  For more information, see the following article:

  Advanced troubleshooting tips for General USB for Windows XP problems

  http://support.Microsoft.com/kb/310575

  Hope this information is useful.

  Jeremy K
  Microsoft Answers Support Engineer
  Visit our Microsoft answers feedback Forum and let us know what you think.

  If this post can help solve your problem, please click the 'Mark as answer' or 'Useful' at the top of this message. Marking a post as answer, or relatively useful, you help others find the answer more quickly.

• Error "one of the USB devices attached to this computer has malfunctioned and Windows does not recognize it." when you connect Logitech M225

  Original title:

  My wireless mouse works fine for the last 2 months, now, all of a sudden it doesn't work at all.

  I get a windows notification that says-

  "One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it."

  I have Vista 32 bit OS on my laptop.

  My office has Windows 7 32 bit and I am able to use the mouse on this computer, then the M225 is not defective.

  I tried to look for a download of update on the site of Logitech & only found:

  6.32.20 set - point it did nothing to help.

  I also tried to move the receiver to the other 2 ports USB w / still the same results.

  Are there other downloads or solutions that will help w / this problem?

  You can also try searching for devices strangers (with yellow symbols) in the Manager under the mouse devices and other pointing devices and other devices (if any). Right click and uninstall unknown devices. Then restart.

  Also try the steps below to reset the power of USB:
  (a) the laptop off, unplugged from the wall outlet.
  (b) remove the battery for a few minutes, then reinstall it.
  (c) then restart the laptop.

• Windows 7 and install/recognize the problems of printer HP LaserJet P2015 error - USB Device not Recognized One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it.

  Title: Windows 7 and install/recognize printer HP LaserJet P2015 teething problems...

  I have a dell inspiron that was originally windows Vista and I changed to windows7.  I have a LaserJet where I work, a HP LaserJet P2015 printer and when I plug in the USB, it says (peripheral USB not Recognized One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it.

  How and what should I do to get the printer going or to get the computer to recognize.  Installation CD will not work and I looked online and downloaded drivers but still the same thing.

  Hi LOliver,

  Method 1: Run the hardware and peripheral troubleshooting tool and check if it makes a difference.

  Open the hardware and devices Troubleshooter

  http://Windows.Microsoft.com/en-us/Windows7/open-the-hardware-and-devices-Troubleshooter

  Method 2: Disconnect all USB (Universal Serial Bus) devices connected to the computer (unless your mouse and keyboard). Connect the printer and check to see if the problem persists.

  Method 3: Connect the printer to a different USB port and check.

  Method 4: Reinstall the USB (Universal Serial Bus) controllers.

   First of all, please disconnect all USB devices and then perform the following steps:

  (a) click on 'Start', type device manager in the search bar and press "Enter." If necessary, click on continue.

  (b) in Device Manager, double-click to expand the "USB Bus controllers", right-click on the "host controller", click "Uninstall" and click "OK".

  (c) repeat step 2 to uninstall all items under 'USB Bus controllers'.

   

  Then, restart your computer and windows will automatically reinstall all USB controllers.

   

  HP printer drivers- ensure that you download the driver appropriate for your device model package.

   

  Thanks and greetings

  Ajay K

  Microsoft Answers Support Engineer
  ***************************************************************************
  Visit our Microsoft answers feedback Forum and let us know what you think.

• Error: One of the USB devices attached to this system has malfunctioned, and windows does not recognize it.

  tried already everything written here. When I plug my USB device (3 of them) my Windows a sad of the USB devices attached to this system has malfunctioned, and windows does not recognize it. I tried plugging it into another winXP machine, it won't work. Can you help me?

  Original title: usb malfunction

  His salvation,

  Thanks for posting your query in Microsoft Community Forum.

  1. What are the troubleshooting steps you have tried so far?
  2. If it works much earlier? If so, did you do changes on the computer before this problem?
  3. What type of USB device you are using?

  As you mentioned that the USB device does not work when plugged into a WinXP machine, it may be a problem with the device itself. In addition, the question may also arise if the currently loaded USB driver has become unstable or damaged or if your PC requires an update for problems that could conflict with a device USB and Windows.

  Therefore, I suggest you try the following methods (skip the ones that you already tried) and check if the problem persists.

  Method 1:

  Please try the fixit (s) provided below which will help you solve common problems associated with devices and USB ports.

  • Hardware devices do not work or are not detected in Windows
  • Diagnose and automatically fix the Windows USB problems

  If method 1 does not work, try Method 2.

  Method 2:

  Remove and reinstall all USB controllers.

  1. Open Manager devices by clicking the Start button, click Control Panel, click system and security, and then, under System, clicking Device Manager. If you are prompted for an administrator password or a confirmation, type the password or provide confirmation.
  2. In the list of the categories of equipment, locate and expand Bus USB controllers.
  3. Right-click every device under the Bus USB controllers node and then click Uninstall to remove them one at a time.
  4. Restart the computer and let the USB controllers get reinstalled.
  5. Plug in the removable USB device and test to make sure that the problem is solved.

  If the problem persists, go to method 3.

  Method 3:

  This method will install the latest drivers from device to your USB device.

  1. Click the Start button, type Windows Update in the search box, and then click Windows Update in the results pane.
  2. Click find updates. When the scan finished, click optional review updates.
  3. Click the check box next to the update, and then click install updates.
  4. If you are prompted, read the license agreement, then click I agree.
  5. Follow the instructions on the screen to download and install updates.
  6. If you are prompted, restart your computer.

  More information: Update a hardware driver that is not working properly

  If the device fails after updating the driver, you can try to roll back the driver with its previous version.

  Restore a driver with its previous version

  Hope this information is useful. If the problem still persists, please post back for further assistance, we will be happy to help you.

• We get an error "device is defective, Windows does not recognize ' when connecting Smartparts SP1100B 11

  * Original title: Smartparts SP1100B 11 "LCD Digital picture frame

  AC power cord pluged, switch works / stop, photo do not shine as if no power is being photo frame. I pluged USB cord in my PC and it says device has malfunctioned and Windows does not rscognize it. It is compatible to my PC system. What should do?

  Hello

  I suggest you to follow the steps below and update us with the results.

   

  Method 1: Run the hardware and devices Troubleshooter and check.

  http://Windows.Microsoft.com/en-us/Windows7/open-the-hardware-and-devices-Troubleshooter

  Run Microsoft Fixit and check.

  Hardware devices do not work or are not detected in Windows

  http://support.Microsoft.com/GP/hardware_device_problems

   

  Method 2: Reinstall the USB controllers.

  This method addresses the steps where the USB driver currently loaded became unstable or corrupted.

  a. click Start, type device in the area Manager Search , and then click Device Manager.

  b. expand Bus USB controllers. Right click on a device, and then click Uninstall. Repeat for each device.

  c. Once complete, restart your computer. Your USB controllers will automatically install.

  d. check the issue.

  Let us know if it helps!

• I can't access firefox, everytime I try I get that windows does not find the file, I tried it redownloading but he still gave me the same message?

  I can't access firefox, everytime I try I get that windows does not find the file, I tried to download again, but he still gave me the same message. the problem has nothing to do with my internet because it freaks on the internet explore and everythign is fine, just my computer can not access firefox for some reason any. I tried uninstallign it and then install again, but that did not work, I tried to install a different version and it still doesn't work.

  yesterday

  User Agent

  Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; MSDigitalLocker; FunWebProducts; GTB6; .NET CLR 2.0.50727; InfoPath.2; .NET CLR 1.1.4322; OfficeLiveConnector.1.3; OfficeLivePatch.0.0 .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

  I'm sorry, but you have not answered my questions.

  (1) on the last stage Setup lets you start Firefox, if you keep all of the checkbox "Launch Firefox now", turns on Firefox when you click on "Finish"?

  (2) how did you launch Firefox when you receive the error message? How do you 'by clicking on the freshly installed target Firefox.exe?

  (3) what is the exact error message? (Post a screenshot if you cannot re-type precisely). Text you have posted it lacks an ending quotation mark and does not resemble any message I know.

• Windows does not start after the update...

  Hope someone can help with this,

  I just installed the update sp1 for my computer for Windows Vista Premium Home dir all installed with no problems, but when I restarted my pc, Windows wouldn't start. The only thing that is on display is a black screen with Windows Error Recovery on top, then he said "Windows does not start. A recent hardware or software change might be the cause. I tried to restart it in different ways, but nothing. Then he said: I have to insert my OS drive to try to fix, but that's not even start. Everyone knows about this problem? This has happened right after that I installed the update...

  L.Butler,
  Are you able to boot from your Vista DVD or recovery partion and run the Startup Repair tool?  If you do not have a Vista disc so make sure that your computer is configured to boot from the CD drive before booting from the hard drive.  Once you start with support for Vista select the "Repair your computer" option and first run "Startup Repair".  If that is not correct the problem then boot with Vista support and select the option "System Restore" and choose a date prior to the update install.
  Once you are able to boot normally again, then I suggest that you are looking for virus\malware.  SP1 was released in April 2008.  So if you install earlier means there may be other problems on your system.  If you have a backup of your current personal data then I recommend to do a clean restore to install\factory.  Then immediately install antivirus software, and then do all Windows updates before installing other software. Mike - Engineer Support Microsoft Answers
  Visit our Microsoft answers feedback Forum and let us know what you think.

• EXPLORE WINDOW DOES NOT...

  I HAVE WINDOW VISTA ORIGINAL BUT STILL I START MY COMPUTER LAPTOP IT ALWAYS GIVE ME AN ERROR THAT EXPLORES THE WINDOW DOES NOT WORK.

  CAN U PLEASE HELP ME HOW TO SOLVE THIS PROBLEM...

  AND I BUY GTA VICE CITY, BUT HE PLAYS IS NOT ON MY LAPTOP IT SHOWS VICE CITY. EXE STOP WORKING...

  Hello

  Please do not type in capital letters as it is difficult to read and regarded as yelling.

  What antivirus/antispyware/security products do you have on the machine? Be one you ALREADY had on this
  machine, including those you have uninstalled (they leave leftovers behind which can cause strange problems).

  ----------------------------------------------------

  Follow these steps:

  Start - type this in the search box-> find COMMAND at the top and RIGHT CLICK – RUN AS ADMIN

  Enter this at the command prompt - sfc/scannow

  How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program
  generates in Windows Vista cbs.log
  http://support.Microsoft.com/kb/928228

  Also run CheckDisk, so we cannot exclude as much as possible of the corruption.
  How to run the check disk at startup in Vista
  http://www.Vistax64.com/tutorials/67612-check-disk-Chkdsk.html

  ==========================================

  After the foregoing:

  How to troubleshoot a problem by performing a clean boot in Windows Vista
  http://support.Microsoft.com/kb/929135
  How to troubleshoot performance issues in Windows Vista
  http://support.Microsoft.com/kb/950685

  Optimize the performance of Microsoft Windows Vista
  http://support.Microsoft.com/kb/959062
  To see everything that is in charge of startup - wait a few minutes without doing anything - then right click on the task - bar
  The task manager - take a look at stored by - Services - process - it is a quick reference (if you have
  a small box in the lower-left - show for all users can check only).

  How to check and change Vista startup programs
  http://www.Vistax64.com/tutorials/79612-startup-programs-enable-disable.html

  A quick check to see that load method 2 is - using MSCONFIG and then display a list of the people here.
  --------------------------------------------------------------------

  Tools that should help you:

  Process Explorer - free - find out what are the files, registry keys and other objects processes have opened, the dll
  they loaded and much more. This exceptionally effective utility will show you even owned by each process.
  http://TechNet.Microsoft.com/en-us/Sysinternals/bb896653.aspx

  Autoruns - free - see what programs are configured to startup automatically when your system boots and you
  opening of session. Autoruns also shows you the full list of registry and file locations where applications can configure auto-
  start the settings.
  http://TechNet.Microsoft.com/en-us/sysinternals/bb963902.aspx
  Process Monitor - Free - monitor the system files, registry, process, thread and DLL real-time activity.
  http://TechNet.Microsoft.com/en-us/Sysinternals/bb896645.aspx

  There are many excellent free tools from Sysinternals
  http://TechNet.Microsoft.com/en-us/Sysinternals/default.aspx

  WhatsInStartUP - free - this utility displays the list of all applications that are loaded automatically when Windows
  starts. For each request, the following information is displayed: Startup Type (registry/Startup folder).
  The command - line String, product name, file Version, company name, location in the registry or the file system,
  and much more. It allows you to easily disable or remove unwanted programs that runs in your Windows startup.
  http://www.NirSoft.NET/utils/what_run_in_startup.html

  There are many excellent free tools to NirSoft
  http://www.NirSoft.NET/utils/index.html

  Window Watcher - free - do you know what is running on your computer? Maybe not. The window Watcher says it all, reporting of any window created by all running programs, if the window is visible or not.
  http://www.KarenWare.com/PowerTools/ptwinwatch.asp

  Many excellent free tools and an excellent newsletter at Karenware
  http://www.KarenWare.com/

  ===========================================

  Vista and Windows 7 updated drivers love then here's how update the most important.

  This is my generic how updates of appropriate driver:

  This utility, it is easy see which versions are loaded:

  -Free - DriverView utility displays the list of all device drivers currently loaded on your system. For
  each driver in the list, additional useful information is displayed: load address of the driver, description,.
  version, product name, company that created the driver and more.
  http://www.NirSoft.NET/utils/DriverView.html

  For drivers, visit manufacturer of emergency system and of the manufacturer of the device that are the most common.
  Control Panel - Device Manager - Display Adapter - note the brand and complete model of your
  video card - double - tab of the driver - write version information. Now click on UPdate Driver (this
  cannot do anything as MS is far behind the certification of drivers) - then do a right click - Uninstall - REBOOT
  This will refresh the driver stack.

  Repeat this for network - card (NIC), Wifi network, sound, mouse, and keyboard if 3rd party with their
  own the software and drivers and all other main drivers that you have.

  Now go to the site of the manufacturer of system (Dell, HP, Toshiba as examples) (restoration) and then of the manufacturer of the device
  (Realtek, Intel, Nvidia, ATI, for example) and get their latest versions. (Look for the BIOS, Chipset and software)
  updates on the site of the manufacturer of the system here.)

  Download - SAVE - go to where you put them - right click - RUN AD ADMIN - REBOOT after each installation.

  Always check in the Device Manager - tab drivers version you install actually shows up. This
  because some restore drivers before the most recent is installed (particularly that audio drivers) so install a
  pilot - reboot - check that it is installed and repeat if necessary.

  Repeat to the manufacturers - BTW on device at the DO NOT RUN THEIR SCANNER - manually check by model.

  Look at the sites of the manufacturer for drivers - and the manufacturer of the device manually.
  http://pcsupport.about.com/od/driverssupport/HT/driverdlmfgr.htm

  How to install a device driver in Vista Device Manager
  http://www.Vistax64.com/tutorials/193584-Device-Manager-install-driver.html

  If you update the drivers manually, then it's a good idea to disable the facilities of driver in the Windows updates,
  This leaves ONE of Windows updates, but it will not install the drivers who are generally older and cause
  questions. If updates offers a new driver and then hide it (right click on it) and then go look for new ones
  manually if you wish.

  How to disable automatic driver Installation in Windows Vista - drivers
  http://www.AddictiveTips.com/Windows-Tips/how-to-disable-automatic-driver-installation-in-Windows-Vista/
  http://TechNet.Microsoft.com/en-us/library/cc730606 (WS.10) .aspx

  Hope these helps.

  Rob - bicycle - Mark Twain said it is good.

• Need help! This version of Windows does not support this version of Windows Media Technologies.

  I got this error message when I tried to install Hotel Giant 2. Don't really know what to do... Pls help! Contact Microsoft Corporation support This version of Windows does not support this version of Windows Media Technologies. This product, which was created by Microsoft Corporation, has been blocked from running because it can prevent your computer from starting correctly in the future. Recommendation

  Hi Dot77,

  Thanks for posting on the Forum of answers.

  I suggest to download the patch from the site Web of Nobilis.

  I hope this helps.

  Chris
  Microsoft Answers Support Engineer
  Visit our Microsoft answers feedback Forum and let us know what you think.

• My pc says that windows does not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM.

  My pc says that windows does not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM. It is said it can be repaired by using the original installation CD, but we do not have. Any ideas please?

  The file is missing or corrupt is one of your files in the system registry.

  By far, the best way to recover from this is to go to another computer and create a free Hirens Boot CD.
  Download Hirens: <> http://www.hirensbootcd.org/download/ > (link at the bottom of the icon of the disk)
  Hirens CD burning <> http://www.hirensbootcd.org/burning/ >

  Once you create the CD, and then start your system of problem with this CD.  In the first window, select "Mini Windows XP" and wait for the system to start.  When it starts, go to the Hirens Boot CD menu and select
  Register-> Registry Restore Wizard.
  then follow the prompts.  This wizard will return a copy of your registry database from backups that are stored with your system restore points.  After the restoration, stop, remove the CD and restart.

  When you start your system, it is recommended to perform a system restore operation to ensure the consistency of your system
  "How to restore Windows XP to a previous state"
     <>http://support.Microsoft.com/kb/306084 >

  Also, this error is almost always accompanied, if not caused, the corruption of the file system.  Also a good idea to perform a check disk (chkdsk) operation with the option "repair".
  "How to perform disk error in Windows XP check"
     <>http://support.Microsoft.com/kb/315265 >

  The hard way to get back is covered in the following Microsoft KB article, but if you have installed a large number of service packs for your installation of XP, I don't give you many chances to get past part 1. (And there's also an installation CD to access the Recovery Console)

  "How do I recover from a corrupted registry that prevents Windows XP boot"
    <>http://support.Microsoft.com/kb/307545 >

  HTH,
  JW