still on your computer that Mawarebyte's did not detect; I recommend you install Super AntiSpyware http://download.cnet.com/SuperAntiSpyware-Free-Edition/3000-8022_4-10523889.html?tag=mncol or F-Secure's Easy Clean http://www.f-secure.com/en_EMEA/security/tools/easy-clean/ before we start looking at possible O/S issues
My computer is a dell dimension E521 dual core with vista, Microsoft Security Essentials, Malwarebytes' Anti-Malware, and Mozilla Firefox as my browser, for years. I was some place where I should not have been, and got an STD and herpes, which Microsoft Security immedately told me about,and Malwarebytes got rid of, two Trojans. Now I have to re-set Firefox everyday, and reboot, in order to get it to open. When I opened the Firefox file, there's a Blocklist.xml posting in there in red that says blocklist xmins. I have un-installed Firefox and re-installed with a fresh download, but I still have to reset it in default every day to get it to open, next day, have to reset it again.........Please Help Me...

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