You may be a victim of software counterfeiting

This copy of windows did not pass genuine windows validation.
Ask for genuine microsoft software
To fix and Resolve the problem you may follow these steps:

After installing your genuine copy of Microsoft Windows XP you are prompted with a “Your software is counterfeit” error message at startup. Even after visiting the www.microsoft.com/genuine/ site and validating, you still get the above message popping up after 2 or 3 boots. There is an easy solution to this and I would like you to follow the steps below to fix the issue.

1. C:\Windows\Downloaded Program Files

• Within that folder, remove any files or folders associated with .WGA

2. Safe Mode

• Reboot your computer and as soon as Windows logs off, start repeatively tapping the F8 Key on your keyboard.
• As soon as you see the Windows Advanced Startup options select Safe Mode within Safe Mode get yourself into these folders…
• C:\Windows\System32 (Rename wgatray.exe to wgatrayold.exe)
• C:\Windows\System32\dllcache (Rename wgatray.exe to wgatrayold.exe)
  Note: Dllcache is a hidden folder, to view hidden folders do the following, go to Start, Control Panel, Folder Options,
  Select the view Tab and under the Hidden Files option, select Show hidden files and folders

3. Safe Mode Registry

• Click on Start, Run and within the open dialog box type regedit and click OK.
• Within the Registry Editor navigate your self to
  HKEY_Local_Machine\Software\Microsoft\WindowsNT\CurrentVersion\Winlogon\Notify\WGALOGON
• Right Click and Export the WGALOGON Folder (this should be saved onto your machine for backup purposes)
• After Exporting the folder, DELETE the WGALOGON folder
• After deleting close all applications and Restart your machine back to Normal Mode

4. www.microsoft.com/genuine

• Get into the site above and manually re-validate your copy of Windows.
• After being prompt of a successful validation, Restart your Machine.