It sounds like your computer might be infected with a Virus ([http://www.bleepingcomputer.com/forums/topic446165.html http://www.bleepingcomputer.com/forums/topic446165.html] ) I suggest the following resources: [[Is my Firefox problem a result of malware |Is my Firefox problem a Result of Malware]] is a Mozilla Support article with some good tips on avoiding and fighting malware. To double check your system is clean, do the following (Not official Mozilla advice, just good practice from personal experience) Download and Install MalwareBytes Anti-Malware, run a full Scan. [http://www.malwarebytes.org/ http://www.malwarebytes.org/] Download and Run TDSSKiller [http://support.kaspersky.com/faq/?qid=208283363 http://support.kaspersky.com/faq/?qid=208283363] Download and Install Microsoft Security Essentials [http://windows.microsoft.com/en-US/windows/products/security-essentials http://windows.microsoft.com/en-US/windows/products/security-essentials] (not an official endorsement, but I personally recommend MSE as an awesome permanent anti-virus) Double check for all Windows Updates. If you are still having problems with Malware after that, I would recommend either [http://www.bleepingcomputer.com/virus-removal/ http://www.bleepingcomputer.com/virus-removal/], or having your computer cleaned by a professional.

I ran TDDSKILLER and it found and removed 1 rootkit program. A few weeks ago, I ran Malwarebytes and it messed up my computer. Can you suggest another malware software? I have Windows 7 Professional 64-bits on HP laptop. Also, I had MS Security Essentials running on my laptop for over 6 months. It does a update and full scan daily. Thank you for your advice!

Seems to have worked ... and worked well!