PROBLEM SOLVED
on my Toshiba Satellite Windows 7
Hi, I had the same problem with a Toshiba Satellite laptop, I found the problem: Trojans.
Heres is what I did:
Start your laptop, and while it is booting press F2
a boot menu options appears, select something with command prompt ( I do not remember exactly the words)
Now a command prompt window will appear, just type: explorer.exe
this will load windows in safe mode.
Now download this little but powerfull program: Rkill from this site: http://www.bleepingcomputer.com/download/rkill/ (if you have another computer download it there, put it in a usb flash drive then run it in your afected laptop, this is what I did)
What Rkill will do is stop any malicious process, so you can run a antimalware program.
After you run Rkill, download this antimalware program : Malwarebytes from this site: http://download.cnet.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html run it, select Quick scan, after the scan, select the afected files and select remove. After this it will ask you to restart your computer.
It worked for me!
I hope this will work for you guys, please let me know