Lets look at the pc first to see if there is any outside problem:
Download
HijackThis from here
[Only Registered and Activated Users Can See Links. Click Here To Register...] . It will create
a directory folder for you in C\Program files.When you run the progam,check for updates.
Doubleclick HijackThis.exe icon. Press the <Scan> button.
Do not scan in safe mode.
DO NOT FIX ANYTHING YET!! Most of the entries found in a HiJackThis scan are programs/files which are REQUIRED for your
computer to operate normally.
Press the <Save Log> button and save into your HJT folder.
The log should automatically open in Notepad.
Copy/paste the results to the forum and let an expert evaluate it for you.
Close HiJackThis//
Important: Close all windows/programs, internet connections and especially internet browsers before scanning and fixing with HJT.