there are a few things you can try first if this is a dell dimension desktop with an audigy 2 soundcard in it try this fix
Open the MSCONFIG utility (Start/Run type in MSCONFIG click OK) and deselect (uncheck) the /L:ENG entry from
the STARTUP tab, click Apply, click OK and restart your computer.
if it is not also try this one
Click on Start/Run and type regedit and click ok. Then navigate
version/winlogon. In the right box go to shell it should read Explorer exe
windows\system32\system32.exe Right click on shell open modify and delete
windows\system32\system32.exe. LEAVE EXPLORER.Exe.in tack and reboot.
and if none of those work go here and go to number 260