Locked files : Access Denied or Used By Other Program


After installing Comodo PF version 3, I also installed Comodo AV. Since then when I try and alter or delete files I get an error message that notifies me that the file is in use - Access denied or, Is In Use by another program. I thought it might be BOClean so I uninstalled it but no luck.

Before I go thopugh the process of elimination and uninstall CPF and CAV, has anyone come across this problem?

I’m running XP sp2 and logged on as Administrator. There is no other AV or FW installed. However, Windows Defender is installed and running, although there wasn’t a problem with CFW ver 2.

I also thought that it might be caused by programs that are in the Pending area, but after either removing or moving them into My Safe Files, the problem still persists.

Interestingly, if I reboot and delete the files previously locked, the delete works. However, after a short while I again cannot delete or alter files!

Please help - Thank you


If CFP is the culprit, there should be Events in the View Defense+ Events page. Check there for any info.
EDIT: There may be a conflict, either in the two (Windows Defender & CFP) working together or during installation. The working together conflict is my bet. I would guess that you need to put the Windows Defender exe’s onto the My Own Safe Files list by browsing for them (Defense+>Common Tasks>My Own Safe Files). I don’t know WinDef, but I would guess that there is a similar way to exclude the CFP processes from being scutinized. CFP may not play nice if it is being scanned - it protects its own processes in memory and on the disk.

It is possible that this may be due to CAVS. There have been reported problems of CAVS locking files so it may be worth uninstalling CAVS to see if this solves your problem.

There will soon be a new, much improved version of CAVS that will work nicely with CFP to protect your pc. If it turns out that CAVS is locking the files in your case then you could always try something like Avast until the new CAVS is ready.

It is also possible that windows defender may be the cause but I would try and eliminate CAVS first. If uninstalling CAVS does not fix the problem then it is likely a clash with windows defender.


You could try using a utility like Unlocker:


To help establish which application is locking the file.