Windows 7: Unable to save MSoffice files (excell, word, etc) on C

Its been a week now since i have this problem that im unable to save MSoffice files on my laptop's C drive. I keep on getting the message "Your changes cannot be saved to "fxx.xxx" because of sharing violation."
This started when i removed my membership from administrators group to power user and change the owner from me to administrators group, i did if for standard security setup in our office for all computers (im part of administrator team, so i know the admin password anyway). Since then im not able to save any MSoffice file on c.
So far this is the only program that i know of that wont allow me to save files on c although i tried running a standalone program from D (no installtion required) and create a profile/or user for that parcticular program, then close the program and open it again but the profile is not being created. I tried doing it using admin login and it is able to create i can also save MSoffice file on c. Funny thing is, on the other machine the same standard security set up is working for a power user. i tried reinstalling the msoffice XP program but to no avail. I tried adding my name again on the administrators group stil not able to save.

would setting yourself up with a new account plus admin privileges work..?

Are you trying to save your files to the root of the C drive? or does it just not save in any location on the C drive?

Thanks for all your replies..

Bugmeistaer - my account used to be a member of admin group in which i have never an issue, for security standard purposes, i removed my membership on the admin group that when the problem started, after a week i tried adding my account to admin but the problem still persist.

Rei Tumult - I couldnt save anywhere on the C drive.

See this.

Sharing Violation error when saving an Office 2007 document in Windows 7

Are you by any chance using Trend Micro? This is a known issue, if yes try using another AV.

What you can also try is create a folder on C: drive, take ownership of that folder, then save Office files in that folder.

Take Ownership Shortcut

Bill2 - Your suggestion is just a work around ( just incase if it works), if i have 200 client that encountered the problem..it is a no no...i can consider the trendmicro issue..but i have other machine which is working perfectly and take note that user on the other machine is not even a member of admin group or power user, just plain domain member..how come everything works pefectly for that user. although the owner is the "trusted installer..*)#@$%$..I FOROT THE EXACT ID)..but anyways the owner is not the administrator..So i still believe 90% percent it is more on security issue but couldnt figure out which security settings i need to ammend as other machine works prefectly...

Just to add uo..before on this machine i was a member of the admin group and was the owner of the drive( ownership) now the owner is the administrators..but i still believe that i still should access or able to save on the drive C even if just a regular user as for other it is working,,

Does the power user username/group have explicit rights to the C: drive.

As windows 7 local users are by default only allocated to either the administrators or users groups - the power users group is not allocated any rights by default but is retained for compatibility - check that the groups are allocated and assigned correctly