Random DOS prompts popping up

At random moments, a series of Command Prompt windows (often 3) opens up on top of whatever programs I may be running. It occurs regardless of whether I am online and regardless of whether I am actively using any programs on my desktop. The prompt says this: C:\windows\system32\cmd.exe
The problem began almost a year ago, and I have tried several malware scans to determine the issue with no luck.
I have followed the READ AND RUN ME FIRST post with the exception of the ComboFix step. Even after I removed AVG, ComboFix still brought up an AVG conflict error message, so I skipped that step.
I could not recall where the SuperAntispyware Log was saved, so I ran it again, and am posting the second log (the first run was clean).

Thanks in advance for your help.

 

Thank you for your quick reply!
I updated to the latest versions and gave it a go. When I ran combofix, I got a message about AVG being active, even after I thought I had uninstalled AVG. I ran combofix, disregarding the warning. Log is attached.
Before I ran MGtools, I ran the AVG uninstaller again, and I think the removal worked.
MGtools and Malwarebytes logs are also attached.
I also removed a-squared Free 3.1.
Thanks again for your assistance.

 

The same issue is still occurring. For example, when I was attaching the logs on the previous message, three consecutive windows popped up in rapid succession on top of my browser and disappeared just as rapidly. From time to time the windows stay up long enough for me to see that they say C:\windows\system32\cmd.exe.
-m

 

Thanks again, TimW;
I just want to clarify: by "last tab" do you mean the "startup" or "tools" tab (or possibly "services")? The reason I ask is the "tools" tab is the last one, and I can't see anything to uncheck.
Thanks for your help.
-M

 

Alright. I followed the instructions, and so far have not had the popping windows return, however, I do have procedural questions:
As I go down the list, checking two boxes at a time, I then click "Apply?" This is what I did.
How long should I wait to see the "issue" before moving on to the next two startup items? I waited 10-20 seconds each time, but since the "issue" is random, I was unsure how long I should wait before moving on down to the next items on the list. After waiting briefly I followed the described procedure, and ended up with all boxes checked, but no return of the issue.
I will keep my eyes open in the mean time.
Thanks again for all of your efforts so far!
-M

 

Thanks TimW,
I have not yet isolated the culprit startup item, but the good news is, so far after several days, no more issues have arisen. At least now I know where to begin again if the issues return. Thanks for your patience and insight!