Complete and total system lockups

I’ll start with a little background. About 2 months ago I began experiencing random, total system freezes on my old PC (Windows 7 x64). They would occur randomly sometimes minutes after startup, sometimes hours. They were not repeatable and I could not figure out anything that induced them. There was no indication as to what the problem was either - no blue screen, no “program not responding” or “program has stopped working”. Nothing meaningful or pertinent in windows event viewer. My system would just FREEZE, sometimes I could still move the cursor but if I pushed the issue and tried closing or minimizing an open window or opening a context menu the cursor would freeze too and I would have no input to the system at all. No ctrl-alt-del, nothing. Only a reboot would fix it until it happened again, unpredictably. I was pulling my hair out trying to figure it out. I was beginning to contemplate hardware issues, everything under the sun.

Fast-forward to a month ago. I put together a new machine (Win 7 x64 on this one too). I reformatted the old machine (still Win 7 x64) and left it as a plain Windows installation and set it aside for a friend to use and run it how he wanted. Avast has not been on the old machine since its been reformatted. Once I had my new machine setup I decided to evaluate a different AV just out of curiosity. Both machines have been running perfectly for the past month. Then my trial ran out on the other AV so I went back to Avast and not ten minutes after finishing the install my new machine totally freezes just like the old one did before. I believe I finally found the cause of my freezes. I’ve used Avast for years and never had any problems and I can’t recall any major changes in my system around the time this all started happening so I’m wondering if it’s specific to the newer builds or even if Avast is actually to blame rather than maybe some adverse interaction with other software on my computer.

So, bottom line, has anyone else had any issues like this? Avast has been uninstalled from my system but I am willing to give it another go if someone has solid suggestions for a fix. What can I look for as far as logs or other info to help pinpoint the issue?

  • Which Avast…? (Free/Pro/IS/Premier)
  • Which version…?
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?

Internet Security
Most current version at time of occurrence.
Malwarebytes Anti-Malware also installed - I’ve had this installed alongside Avast going back a couple months before the problems started and never experienced anything indicating a conflict.
I installed Malwarebytes after experiencing a browser hijack that Avast could not remedy. Malwarebytes took care of it.
Avast IS was the only AV ever installed on the old machine.
Kaspersky IS was installed on my new machine prior to Avast IS.

First, be sure to get rid of all remnants of your prior installed AV(s)…!!
https://www.avast.com/faq.php?article=AVKB11

Then:

  1. Download Avast Internet Security: https://files.avast.com/iavs9x/avast_internet_security_setup.exe
  2. Follow instructions: https://www.avast.com/uninstall-utility (Run this tool for all prior installed Avast versions…!!)
  3. Reinstall Avast with the downloaded installer from point 1.
  4. Reboot.