Windows installer problems

Hi. Just registered here because this seem like a great place to ask for help.
I hope you can help me with a problem that's extremely annoying...

Some days ago my "Windows installer" stopped working. I have tried this but it doesn't help.
If I restart my PC windows installer works for a few minutes, but all of a sudden just stops working.
I have no idea what has happened. I have been googling about it alot but without any result...
If I check out the service it says it's set to automatic startup, and when it do stop working and I try to re-enable it I just get an 1053 error message (It's very hard to translate the message so you would understand it, though, so I didn't type it here. I use Swedish XP).

I can't install anything without it, and that's extremely annoying. I would like to avoid reinstalling XP so if anyone have any idea what I can do to fix this I would be VERY thankfull.
I've done malware and virus scans but it doesn't find anything. I am running an online scanner at the moment but no result so far, and it's almost done.

I use Windows XP SP2. I just uninstalled SP3 to see if that would help but it didn't.


Thanks in advance.

 

Have you tried windows installer cleanup?

http://www.majorgeeks.com/Windows_Installer_CleanUp_Utility_d4459.html

 

I sure have. Didn't help at all unfortunately.

 

Aah why didn't I think of that... unfortunately the earliest system restore is like 2 days after I got that problem.

I do have an old backup of my harddrive, but using that one would almsot be as bad as doing a clean install... I guess it's leaning towards an install/backup install.
I wonder what's causing this though. I just restarted the PC and when I check in services it's working perfectly. But in a few minutes I know it will stop


EDIT: Forgot to mention that I have tried different versions of Windows installer but I get the same probmel no mather what version I use.