Hi. I will see if I can explain this. I ran into some problem and did a lot of checking. A friend who does computer support urged me to come here and ask if I’m overlooking some things that need to be done. I’m no expert, but here’s what happened.
I was hunting down some adware that had invaded IE and Firefox. I figured out which browser addon was causing it. It was a fastfreeconverter-somoto addon that had sneaked its way into my computer. It was showing ads from ad.reduxmedia. I disabled this and searched for its files on my computer. Removed those. All this was done by hand. No help from malware or AV software. The ads are gone. But...
A friend suggested I also run Malwarebytes. It found a backdoor agent file called Set.bin, which it quarantined. Here's some information I found on an AV website.
Anyway, it’s supposed to have a csrss.exe file in the same folder. I didn't have it. But I found two csrss.exe files elsewhere.
According to a few websites, any csrss.exe file other than the one in System32 should not be there. But in the Microsoft forum they said it's okay in that kind of path. http://answers.microsoft.com/en-us/protect/forum/mse-protect_scanning/csrssexe/26bba20c-2691-4d42-bec4-637436c53c4f.
So I compared the files and they have identical in size, date, CRC32, etc. Also, two friends found the same two files in the same folders on their computers, same size and date.
I have Norton Internet Security and had it scan everything. It found nothing that had penetrated the system.
So do you think there are some deeper tools or additional tools I should run? For example, is this the kind of thing that needs one of those rootkit tools, or some other deeper tool?