Need a little help

I wasn't sure where to post this one, but Im desperate for some help.

Logged into my admin account, I cannot do such things as install adobe air on my custom build computer running windows 7.

Things I have tried: 

1) UAC turned off

2) running as admin

3) running in compatability mode (as admin aswell)

4) safe mode

5) net user administrator (in safe mode and out of safe mode, both times as admin.)

I can take a screen shot of the error it gives me.. but it says to the effect of "you do not have permission to install this software, contact a system administrator"

I had a few problems at the start with drivers and thought I fixed it when I took control of every folder (which took a day), but now this.

did you allready tried to create a new user Admin acount?

Do you use some kind of anti-virus? These things love to skrew with your rights.

Anti Virus was the culprit for me, only in rare cases would i recommend re-installing windows. I'm not saying you should re-installing, but its an option.