Error 5 access denied message from Windows when installing other software

Dell with Win XP Pro SP3.

I have Comodo 3 firewall installed, but have had BSOD errors with cmdagent at startup. I therefore have the Comodo service set to manual, and after system starts, I start Comodo service and prog.

IF I forget to do this (i.e. no Comodo element is running), I find that if I download other software for installation then I receive Error 5 Access denied Win error message when I try to install said software.

Question therefore is - what has Comodo set in Windows that affects other software installation/produces Error 5 WHEN COMODO isn’t running?

If I start up Comodo as described above, then installations proceed normally.

Would uninstalling/reinstalling Comodo solve this?

Hi Foxfan100 & Welcome!

Yes, Please uninstall and reinstall. Latest version is here. Can you please also list your security software.


I did that (remove by XP add/remove in CP) and reinstalled. It seemed to hang updating the Virus…(couldn’t see more), but finished, so I rebooted. I immediately got a BSOD which I’m sure is cmdagent yet again. Eventually, I got going in safe mode and found my LAN/Network/Belkin router was unusable (first time I’ve had that ever!), so I’ve had to restore my whole system from an Acronis backup. Not a very good day!

The problems are definitely Comodo, but the problem goes back to BSOD. I’ve not had this until the last 10 days or so, hence my previously described starting mode. Like Topsy, it grew from there.

Windows Defender
Avast av
Spybot (no residents enabled)
Adaware (no residents, free and scan only)

What’s worrying is that a previous software installation attempt (UK Taxcalc update) identified its own installation error as being firewall caused. I can understand this happening when Comodo is running, but it seems a real problem if a non-running Comodo (service and prog. stopped) can interdict other software.

I am now very confused.

Because of the BSOD at system startup caused by cmdagent, I have the Comodo service which runs cmdagent set to start manual i.e. it does NOT run at Windows startup.

However, I have had a BSOD which Win Debug reports as being a cmdguard fault. Rechecking the services shows that Comodo is NOT running.

It is very concerning that all sorts of Comodo stuff seems to be running when to all intents it should not be!