Hi all, this is my first post on this website. AVG keeps flagging up a problem on my girlfriend's computer (running Windows 7 64 bit). It claims that it fixes it, but obviously doesn't as the problem keeps reoccurring. A full scan reveals a nasty called "Trojan Hider.mpr". Rootkit scans reveal something with a name that seems to be randomised with every boot. Spybot S and D reports detects a registry change: 'Microsoft.WindowsSecurityCenter.FirewallOverride' but nothing else.
I've tried scanning with mbr.exe, aswmbr, MBRcheck and all seem to suggest that the MBR is normal for Windows as far as I can tell. I ran GMER (with a randomised name) but this didn't seem to find anything, ditto tdsskiller. I've had to install all of these via a USB from my computer, as hers seems now to have no internet connectivity at all. Someone on this forum (or rather, the forum for reporting logs) seems to have been successful in getting rid of it using combofix in a thread on here, a link to which I can't seem to paste (?). Apart from that thread, one in which someone advises you to dig into the registry manually, and one on mumsnet in which Spybot seemed to fix it, Google isn't showing me anything helpful. I think really I'll probably need help from someone who knows how to use combofix, but thought I'd start here as I don't have any helpful logs to post.
Thanks in advance to anyone who can help.