Malwarebytes Pro is set to start at system startup. I was "doing" nothing other than just starting the computer. The error occurred from the failure of Malwarebytes to start, which started happening AFTER I allowed Avast to make changes to the desktop system. So far, I am not seeing this behavior on the laptop, but because it is a much newer machine, it has a very simple setup without multiple upgrades and the complications that can come from that.
Whichever file was being interfered with to trigger that error apparently was one on the list I provided. Yes, I know it was for an older version, which is why I labeled the file that no longer appears in the current version. Silly me, after four days of no sleep trying to sort this computer mess out and get back to work before what few VCs are watching my project decide I'm too lame to deal with any more, I didn't experiment past the point of getting it to work.
After having run so many tests on these computers, I am convinced that Avast false-positived on something unique to x64 systems. The fact that it threw up the very same malformed rootkit notification (the UI is malformed such that it can't be read) on a brand new laptop as it did on a much older desktop system, and both are x64, while an even older x86 machine that shares a nearly identical setup to the x64 desktop and ALL of the files in common between the x64 desktop and the laptop pretty much proves that there isn't a real infection, or it would have been flagged on the x86 box as well. (I run setups that are as identical as possible on all computers precisely to make maintenance and diagnostic work easier.) The fact that TDSS Killer and all other malware programs I ran all came up clean seems to indicate no problem exists.
After making the settings changes to Avast, both affected systems have calmed down, everything runs as it should, and the desktop system in particular immediately stopped thrashing the hard drive which, along with the malfunctioning programs, I oriiginally believed indicated an active infection. Yet when I set Avast to ask before automatically sandboxing or terminating programs I start, and got through one round of it asking me how to run programs, then added the Malwarebytes file to the whitelist (Avast never asked about Malwarebytes, it just killed it on startup), the last of the bad behavior went away and the machine went back to its normal responsiveness. Even the laptop had slowed to a crawl before I applied these changes and it now is working as expected.
So far, I have not needed to add any Avast exclusions to Malwarebytes on any machine. One reason I have used these two programs together for so many years is that they have a long history of getting along. In fact, when cleaning up other people's computers, I have run both Avast and Malwarebytes together as a "tag team" and watched one flush malware and the other one kill it. I guess those days are over.
I am still considering the fact that this new version of Avast was flagging and stopping some of my game files, but not all of them. They are made with all the same programs and processes and all so far on the same system (desktop x64), and none should be "familiar" to Avast since each is brand new. This inconsistency worries me.
