you have a virus from another pc download to a usb stick malware bytes and hitman pro. boot up into safe mode with networking and run them and see if they remove the virus. also use msconfig look for any toolbars or other 3 party software loaded at start up also run hijackthis to check. in msconfig on the start up tab turn everything off but anti virus. also download the newest version of avg or avast and then uninstall the version you have and try to see if you can remove the virus. if you cant avg and other anti virus people have free virus recovery disks. boot from the disk and try removing the virus.