Sounds like its definately UAC related. This may help: to run a program as administrator once right click on the shortcut and select "run as administrator". To mark a program to always run as administrator right click on the shortcut, properties, shortcut tab, advanced, tick - "Run As Administrator" or right click on the program itself, properties, compatibility tab, "run this program as an administrator"
Just seen the above post. Does the problem go away if you disable UAC? Try that and then we will know if its a UAC problem or something else.