What is cmfdll32.dll and why does it stop working?

Googled, found little, but did find that it is a Comodo file.

PC freezes up and I get a blank screen with the Vista green circle. When I attempt to bring it out of the freeze I get a message to the effect that cmfdll32.dll has stopped working.

Have run AV and Malware scans but nothing shows up.
Comodo diagnostics shows no problems.

Logging off and signing on solves things for a little while.
How to permanently solve this, de/re-install?

This looks, by name alone, to be part of Comodo Memory Firewall (CMF). Which version of CIS do you currently have? Do you have the stand-alone version of CMF installed?

Is it a part of the installed Comodo package v3.10.10.2363.531 (using firewall and defense only). What is a ‘memory firewall’ anyway and why do I need it?

There is nothing about a ‘memory firewall’ showing in the Comodo control panel that I can see.

How to disable/repair if it is not showing in the Comodo control panel?

Since you don’t know what CMF is, I guess that answers the question as to if you had installed or not. Right, CMF - Comodo Memory Firewall was originally a stand-alone product that guards against Buffer Overflow attacks. CMF was later integrated into CIS’s Defense+. The following is from CIS’s Help…

[b]Detect Shellcode injections (i.e. Buffer overflow protection)[/b] - Enabling this setting turns-on the Buffer over flow protection.

A buffer overflow is an anomalous condition where a process/executable attempts to store data beyond the boundaries of a fixed-length buffer. The result is that the extra data overwrites adjacent memory locations. The overwritten data may include other buffers, variables and program flow data and may cause a process to crash or produce incorrect results. They can be triggered by inputs specifically designed to execute malicious code or to make the program operate in an unintended way. As such, buffer overflows cause many software vulnerabilities and form the basis of many exploits.

The actual option to either disable/enable Overflow protection or to exclude programs that conflict with it, can be found under Defense+ - Advanced - Image Execution Control Settings - Detect Shellcode injections.

HOWEVER… slight problem. I’m not convinced that cmfdll32.dll, itself, is actually part of CIS… well not using that name anyway. Possible explanations are: I’m wrong… or you do have CMF (the stand-alone product) installed… or you currently have SafeSurf installed. SafeSurf is a browser add-on (stop-gap?) that included CMF whilst it was being integrated into CIS. Obviously, running more than one Buffer Overflow/Shell Injection protection at the same time might cause problems.

I hope that helps.

Thank you.

The problem simply appeared out of the blue for a couple of days and has not reappeared in the past twenty four hours.

I did not do a search as to where it is located, should have, will do, and take appropriate action to remove it and/or its associated program.

Look in your list of installed programs under Control Panel if you have Safe Surf or Comodo Memory Firewall installed. If this is the case uninstall it or them.