✔ 最佳答案
The symptom was caused by a malware called BlazFind.
Read this page:
http://www.winxptutor.com/wsaremove.htm
and follow the steps. This page deals with another problem caused by this malware first, the second part deals with the logon-logoff problem. So read carefully.
Here are the steps:
1. Boot your computer with Windows XP disc.
2. In the first screen of Setup, press R or F10 to enter the Recovery Console.
3. Enter the administrator password. If you do not know the password, press Enter.
4. You will see the prompt C:\Windows
5. Type CD SYSTEM32 or CHDIR SYSTEM32
6. Type COPY USERINIT.EXE WSAUPDATER.EXE
7. Type EXIT
8. Restart Windows.
You should be able to login successfully. Now you need to edit the Registry.
1. Click Start, Run. Type in REGEDIT to open the Registry.
2. Navigate to
HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ WindowsNT \ CurrentVersion \ Winlogon
3. In the right pane, change the value of userunit from
wsaupdater.exe to userunit.exe,
( include the comma after userunit.exe !!! )
4. Close Registry and reboot.
Your computer should be back to normal.
2007-05-19 05:33:58 補充:
the value in the Registry should be changed toUSERINIT.EXE,not USERUNIT.EXE
參考: My experience. I have this problem before.