windows error no virus

I dont see many stuff on internet about windows errors caused by windows itself not by spy or viruses, why? because nobody know to solve these errors? i have this error for months and and get rid of it. I know to remove any virus or spy, even im not a specialist, but this error is to much.

I get the following error, every time i try to open anything almost

Application log in event viewer.
Event Type: Information
Event Source: Winlogon
Event Category: None
Event ID: 1002
Date: 30/11/2004
Time: 16:35:10
User: N/A
Computer: PC99
Description:
The shell stopped unexpectedly and Explorer.exe was restarted.

The screen goes blank for a second and the task bar and start button disappear then come back.
The problem disapear usually after like 30 minutes of using my PC.

i tried many solutions, almost all. Deleted winlogon and explorer so these can be replaced, sfc scan, all online scanners and all spyware programs. I dont like hjack this, but ok ill try to post the long text one day

 

Seems to be a plethora of reasons for this one, if you can check out this page for starters:
http://www.eventid.net/display.asp?eventid=1002&eventno=826&source=winlogon&phase=1
Lot of causes, fixes too...
puzzled me too

 

yes sorry about the date, i copied the text from a post i found with a problem like mine
Bugballou good link. I think too my problem started after i tried to view some movies or pictures, but i dont see a real solution. And there the solutions are in a database only for members etc

 

Strange, after months, the problem was solved right yesterday, dont know how. Last things i made was a defrag MADE FROM THE OTHER HARD DISK, (i have 2 hard disks, each with windows - so disc c was defragmented when windows was not active) - but i think i made that before too, so probably not this was the solution. Other thing- i enabled some services, because cant use windows update. But strange, these services for windows update are again disabled and i set them to Automatic, no manual. And dont know why my computer description show pack 3 but windows update show i need sp 3... So ill install again, hope nothing ill crash
Also i had to replace a windows file (windows cant start because missing file, i was lucky because i have 2 windows and i replaced the corrupt file). Probably after that my windows update got a strange behavior