"Administrator" Not Working after SP2

I have a wierd problem on one of my computers with XP HOME that started immediately after installing SP2. Even though I am "administrator ", I can not install software in regular mode, saying that I do not have permission. Software updates also do not install saying that I am lacking permission. I can usually install software in safe mode by logging in as administrator (but MS Installer does not work in safe mode). It seems to be an item in the registry (probably a 1 or Zero where it shouldn't be). I have searched the web, MS Knowledge Base, and other resources to no avail. I have found a few other people on GOOGLE who have the identical problem, but no solutions were listed. Any ideas on a resourse or solution?

THANKS!

 

NTFS or FAT32 file system?

 

"Administrator" not working - NTFS

I have NTFS.

THANKS!

 

Consider uninstalling SP2. If the trouble disappears, run AdAware and Spybot to clean up any malwares, scan for virus with latest signatures, disable all startups (including any AV program) and try the SP2 install again.

 

I have done all of that... ;-)

I have already uninstalled and re-installed SP2 twice. I have run updated Spybot Search and Destroy, Ad-Aware, Housecall, Panda, etc.
System is clean.

The computer worked fine before SP2.

The first SP2 install failed, so I restored the original XP HOME; reinstalled SP2, and had the problem; uninstalled SP2, reinstalled SP2, and the problem has been consistant since the first failed SP2 install.

BTW The SP2 I am using is the free CD from MS.

THANKS!

 

Did you do a clean install or a repair install of XP? If the Registry got corrupt from the SP2 install, you won't fix that with a Repair install. I can't tell you where to edit it. A clean install would fix it but that's pretty drastic. Backups needed for sure.

Stick around, maybe someone else will have better advice.