1. either you dont have admin priviledges on you account 2. you might have dowloaded a virus so try the following : a. Update your antivirus and antispyware definition databases. b. Disable your System Restore [start>All Programs>>Accessories>>System Tools>>System Restore>>System Restore Settings>>check Turn off System Restore], c. Clean up all Temporary and Recycle Bins. Use ATF-Cleaner from http://www.atribune.org/ , or use CCleaner from http://www.majorgeeks.com/ d. This step is very important: Boot to Safe Mode, [restart, press F8, choose Safe Mode, login] then run your anti-virus. Clean/Quarantine when necessary. e. In Safe Mode, also scan for spyware, or malwares using Spybot-Search & Destroy https://www.safer-networking.org/dl/ or http://forums.xisto.com/no_longer_exists/ Clean and purge when prompted. You could also verify in SpyBot S&D which processes are running processes or active in Safe Mode. If you see direct link libraries [*.dll], right-click on it to see the properties, if it's not included in your OS, Microsoft if you are using one, or part of your antivirus/antispyware application, you could delete it. Usually malwares have their own *.dll or *.exe services, the gave-away names would be a set of random letters e.g., shdaljd.dll or scvhst.exe, which mimics legitimate OS applications, such as the legitimate Microsoft's svchost.exe.