More about this at http://www.google.com/search?hl=en&safe=on&q=malware+xp+HKLM\SOFTWARE\Microsoft\Windows+NT\CurrentVersion\Winlogon\Shell
And that registry key is noted again at http://www.rarst.net/software/blank-desktop/
I'd take Grif's advice to find the malware and clean it off first. Read 7726-6132_102-5098912.html?tag=posts;msg5099421
At startup, instead of loading the Explorer shell, my computer loads the
File Manager window! I tried going to Task Manager - File - New
Task, wrote EXPLORER.EXE and the same thing happened: the File Manager
(Explorer) window pops up, instead of the Taskbar and Desktop!
How can I fix this?