Login impossible after last Comodo 10 update


Yesterday, I updated 2 of my W7 computers to Comodo
This morning, at startup, I am locked on both at the Windows initial blue screen, without being able to log in. I’m waiting for 3 hours now, but still that Windows initial screen, without the ability to log in.
What can I do ?


Try this:
Boot into safe mode
Start up Comodo
Turn off all protections, permanently
Reboot into regular Windows mode
Enable Comodo protections, but put them in learning mode

I have restored my system to a date prior to Comodo update, using safe mode.
Everything works fine.
I will definitely bypass release…

I have the same problem on Windows XP SP3.
I delete Comodo Internet Security Premium (delete COMODO folder in “Program Files” and comodo *.sys files in “drivers” folder) in safe mode and the problem was solved.
Then I install again CIS After that, Windows again freeze on logon.

P.S. Sorry for my bad english.

Instead of manually deleting files try running the removal tools from this guide.

I made another try and it seems the problem comes from Automatic Sandbox, which is a bit to strong.
I disabled it and have no more identification problems.
Can someone explain me the impact of automatic sandbox on W7 identification ?

Look in the file list, do a search for “unrecognized”, and see what comes up. Maybe you have a system file or a graphics driver that is unrecognized by Comodo, and it gets autosandboxed. Mark all all those important files as trusted. Then enable autosandbox, and reboot.

Nothing was wrong in my unrecognized files.
And the problem is still there. It doesn’t come from autosandbox.

Sometimes, I finally get the W7 login window (1/10), but most of the time (9/10), my PC stays freeze on logon.

IS there a way to configure Comodo in debug verbose mode and send someone a log to try to understand what is appening ?

Thanks anyway.

Try booting into safe mode and disable each component of CIS and then try booting normally.

Hello futuretech,

I did what you said, and Windows froze at startup screen.
I had to reboot 4 times to finally get the login screen.

Any idea to trace what is hapenning ?

Boot into safe mode and uninstall but you need to enable the windows installer service for safe mode follow these instructions. Then after uninstalling from safe mode, boot windows normally and run this tool, (if you have UAC enabled make sure you run the .bat file using run as administrator.) then reboot again. When you login normally, open device manager and go to view menu and select show hidden devices, then expand the non-plug and play driver category and look for any comodo related entries and if found right-click and choose uninstall. Reboot when prompted. Then run the newest standalone installer for the one you want from the release topic here. Do not import any saved config after installing to make sure everything works using a default install.

Also I have to ask do you happen to have any other security software that could be causing issues? Even if it hadn’t before the new update may be more prone to interference with other security software.

Comodo Firewall v6223 doesn’t solve the same problems I am suffering under Win XP SP3. The update fails to fully load Win XP desktop, I don’t know why. The system seems to crash just when Comodo is loading os has just loaded. It’s possible to attempt to restart but the restart doesn’t start.

Hello futuretech,

Thanks for your help. I appreciate !
I’ll do what you suggest, even if I have to lose all my firewall rules and port configuration, exceptions and so on, because I guess that all this will be lost.
Anyway, I’ll do that and let you know.

Concerning the use of another soft, I’m using MAM for as long as I’m using Comodo, but W7 firewall and defender are disabled.
And I’m not surprised to see you talk about that. It is always the same old song. No one wants to admit having introduced a small regression into his last software release. So the problem necessarily comes from the third part which it not compatible with our new software that works much better than before. I’ve heard this for years… But for years, MAM and Comodo did cohabit without the slightest problem.
Installing Comodo could reveal a MAM disfunction. Could be…
But instead of playing ping pong, I’d love to have some Tools to diag the starting of Comodo’s service when my computer starts, to find out what freezes most of the time.
I’ve seen that in the Windows event viewer, Comodo is supposed to log. Couldn’t that be used in some kind of verbose mode, to investigate ? Perhaps then I could find the name of a component that causes the problem.

Uninstalling and reinstalling is a way for me to say “let’s try that first, in case it works, so we won’t burn too much gas investigating…”.

Well, I’ll try what you say…

I’ll inquire about enabling debugging info because I did notice this key which seems to control debugging output HKEY_LOCAL_MACHINE\SOFTWARE\COMODO\CIS\DbgTrace

Well, uninstalling and reinstalling did not change anything.
BUT, I have noticed that Comodo without MBAM works fine and that MBAM without Comodo works fine.
So I have inserted into Comodo exceptions concerning all MBAM files, and now I can start normally and I’m not frozen at startup anymore.
So the Comodo new release was locking a MBAM file at startup, that was necessary for the W7 startup process.

The problem is not resolved by inserting exceptions into Comodo for MBAM and into MBAM for Comodo.
I finally found that the problem comes from Automatic Sandbox that must sandbox a MBAM file, but nothing is indicated concerning which file.
So I have to disable Automatic sandbox in order to get the login window.

What version of MBAM are you using and you say its from auto-sandbox but you have no indication of which file is getting sandboxed, does that mean the sandbox logs does not say what is getting sandboxed? Also maybe try adding install folder and mbam service executables to detect shellcode injections exclusions and turn on auto-sandbox to see if that helps.


I also have problems with logging after Comodo 10 update on WIN XP SP3. After the longing PC simply hangs.
I found that it is possible to log on if I do not start with Internet connected and starts as User but not Administrator. After logging I try different solutions but without any success.
SOLUTION: I found that under INTERNET OPTIONS --General settings – “Initial webpage”, there is not default address but some other strange address. After putting this field to “blank:page”, all the problems with logging in win XP disappear. I do not know which program set the strange address but with blank page (probably also with reset address) everything works OK.