I have a Toshiba Tecra M1 with 1.6Ghz processor and 1024Mb RAM.
My OS is Windows XP SP2.
When I boot my PC and its almost completely done.
I always get the windows installer It gos to 75% and then it closes I got this PROBLEM Yesterday just after I updated my PC trough Microsoft Update.
I don't think its a virus because I have Windows Live Onecare and I've already runed AVG and Spybot S&D.
I've tried to go to the process but its just a little to fast.
Does someone have then same problem with those new update or isn't it that witch caused my problem?

Thanks in advance!
It isn't solved yet I thought that Windows would do that for me but it doesn't.
Its the system process witch causes this problem sow I can't end the process or deactivate it on msconfig.
I don't have any other IDEA how I can check the proces and maybe end it.
is there an other WAY?It SOUNDS LIKE you have an update from MS that didn't finish installing...or a program install that did the same...

Does it do this if you boot into safemode ? ?
If not there is a Windows installer fix that i believe you can run in safemode and should cure the problem...

Link
http://support.microsoft.com/kb/290301

^windows installer cleanup utility .. Thank for the help I installed Windows installer cleanup utility.
I hope this helps.