Application Control Problem [Resolved]

I’ve just starting having issues with Comodo after over a year of trouble free use.

After a while (> 20 entries) in the application monitor, it won’t accept any more automatic entries and I get a blank line at the bottom of the application monitor table.

I’ve tried uninstalling and reinstalling and it hasn’t made any real difference.

Looking at the registry soon after reinstall, there appear to be some ‘pre-existing’ app entries and the first one starts at 20. I’m not sure whether these appear at installation or whether this is coincidence or not. These ‘pre-existing’ entries cannot be deleted from the registry either and they feature applications that are on the PC.

To try and diagnose further I’ve uninstalled Comodo and there’s still 10 entries in
HKEY_LOCAL_MACHINE\SYSTEM\Software\Comodo\Personal Firewall\AppCtrl\Apps that can’t be deleted.

I’m fairly certain that the blank entry problem occurs when it tries to write the 21st application rule (…\apps\20) which clashes with one of the undeletable entries.

I’ve unticked the protect registry entry option so that’s not the cause of the issue.

I don’t know where to go here except reinstall an old backup image.

Now suffering Windows XP Firewall until I can resolve this problem.

Further anlysis of the problem shows that for each of the 10 application rule registry entries that i am unable to delete, there is a subkey 0 which I am unable to access.

I get an error message “Cannot open 0: error while opening key”

I an unable to change the permissions on these entries and XP isn’t able to tell me who the owner is.

Any advice would be much appreciated.

Hey jaydub: welcome to the forum.

Perhaps this recent thread is related?

Soya, Thx for welcome.

Poirot had already pointed me to that thread.

Sounds identical scenario. His fix was to restore to an old back up, which I’d rather not do, if there’s another way of resolving it.

I see…there are really only 2 suggestions remaining from me because as you can see from that thread and the one before (, I couldn’t figure it out:

  1. Clean reinstallation of CFP (e.g. delete all registry keys, install in safe mode)
  2. A ticket to ask official support

Uninstalling in safe mode leaves the undeletable keys behind and they are therefore there if you reinstall.

I have raised a ticket and will have to wait and see what the response is. I assume official support don’t work weekends.

jaydub, I think you may have missed by prior post after I edited and added the other thread link (which was also in Poirot’s thread). That one was resolved without reformat/reimage. To delete the “undeletable” keys, right click on them, select Permissions, and grant yourself Full Control. You must be referring to the legacy keys generated by Windows?

Don’t know if they work weekends. Guess you’ll find out soon :smiley:


Didn’t miss it at all. I already had full permissions and couldn’t delete the subkeys.

I’ve resolved my issue with a system restore from two weeks ago. Decided it was easier than messing about with backups.

I can now delete all Comodo app entries in the registry.

To be fair to Comodo, this occurred at about the same time as i started using RegSeeker as my registry cleaner. I’ve now kicked RegSeeker into touch and am just relying on CCleaner for the time being.

Thanks for your help.

Ah yes. RegSeeker is tempting. I’ve used it and noticed it messed up some icons that I can never retrieve unless I know the registry in & out.

Well, at least your issue is gone despite it not being an official resolution provided by Comodo. I’ll close this thread. PM a mod whenever you need to open it.