Large cmddata file

In the ProgramData folder. A file from comodo takes up 35 GB of valuable space on my SSD. I only found this russian topic on the problem.;msg863527

The solution they mention, is reinstalling. Which is what I’ll be doing right now. I just want to report it, so it’s know this bug appears more than once.

After reinstalling, they file size has reduced to 98 MBytes.

Can you reproduce the problem & if so how reliably?:
One or two sentences explaining what actually happened:
The file cmddata located in “C:\ProgramData\Comodo\Cis\lmdb” has grown to 36GB over time.
One or two sentences explaining what you expected to happen:
The file size should have remained around 98 MBytes
Any other information, eg your guess at the cause, how you tried to fix it etc:
Probably caused by not clean installing updates.

Exact CIS version & configuration: (Pro Active Config)
Modules enabled & level. D+/HIPS, Autosandbox/BBlocker, Firewall, & AV:
Antivirus, Stateful
Auto Contain, Enabled
HIPS, Safe Mode
Virusscope, Enabled
Website Filtering, Enabled
Firewall, Safe Mode
Have you made any other changes to the default config? (egs here.):
Apart from application specific rules, no.
Have you updated (without uninstall) from CIS 5, 6 or 7?:
if so, have you tried a a a clean reinstall - if not please do?:
Yes, this fixed the problem. For now

OS version, SP, 32/64 bit, UAC setting, account type, V.Machine used:
Win10 Pro, 64-bit.

It’s not a known issue. Please use required format.

Do you maybe remember which version you updated to v10?
Did you experience this issue with previous version(s)?

The same issue was described in the Russian section on July 19.

I’ve updated from 8.5 to 9 and to 10. I am pretty sure I have not reinstalled between 9 and 10. I might have between 8.5 and 9.

Hi All,

The Comodo Firewall is installed on my PC (Win10x64).

The cmddata file in the C:\ProgramData\Comodo\Cis\lmdb\ directory is 49.8GB (!!!)

What’s the file is? Should it be so big? How to reduce its size?

Thank you!

That’s odd mine is only 96 MB. Not sure what it related too either. ???

So, how to fix? Just to delete this file? I cannot - only SYSTEM can modify this file…

What data should be kept in this file? Probably it’s related to the system restore/backup?

Is it safe to delete it (if I find a way to do so)?

How to solve? This file should not be so big, it takes about 1/4 of my SSD…

Hi All,

The Comodo Firewall is installed on my PC (Win10x64).

The ‘cmddata’ file in the 'C:\ProgramData\Comodo\Cis\lmdb' directory is 49.8GB (!!!)

Should this file be so big? How to reduce its size? Is it safe to delete it?

Thank you!

Please do NOT double post it is against our forum policy. You can continue your discussion in the help topic you already created.

One thing I would like to see is the stats of the database, download the attachment from this post and after unzipping double click enable_page.reg, then alt-click on any file or folder and select JSON: dump statistics of the database and attach it here. Also state what version of CIS you have installed and how do you update to newer versions of CIS, e.g. do you run the internal updater or do you download and run the installers such as the online web installer or the offline installer.?

I have the same problem. cmddata file is 20GB
Firewall v.
For fix problem. Connect system ssd to other PC and rename file cmddata. After return ssd back, cis created new file cmddata 96Mb

Mine was also 48 Gb. But I have a hybrid HDD, so this is not depending on the disk type.
I fixed it in other way: just unload Comodo from the memory and tried to stop remaining service by attempt to kill it through the Task Manager. Of course it can’t be killed, but it seems it released that file so I could delete them. Now after the launching Comodo again I have the file about 96 Mb too.
So there’s no need to insert your HDD or SSD to the other PC.

This is my first post, so please do let me know if I’m posting it in the wrong place.
I have CIS version running on my computer for over a year now, and I suddenly noticed that a file called cmddata.lmdb has reached the size of 134.1Gb! I researched the topic and read that this file shouldn’t exceed 1Gb tops for any reason. I wonder, can I just delete this file and let CIS create again, hopefully in a smaller size? What do you think is the best course of action here?

Thanks ahead.

You can delete it. It should not grow so big.

You will need to re-install as it will be locked by CIS.


Yeah so I heard but I just deleted it now and there was no problem at all. I hope that no problem should arise in the future.

so im trying to clear somem space on my main hardrive.
suprised and a bit angry to find out that comodo is infact responsible from most of my space take
there is this file called Cmddata.
and it takes like 128 GB.

so 1:what does this file even does?

2:what can i do about him?

It holds all trusted vendors and all information about files from the file list. You should perform a clean re-install as it is the most effective way to reset the database.


Is it normal for the cmddata file to be above 600MB?

Seems to always slowly grow in size, but not over 1GB, even after reinstalling Windows.

I do notice that sometimes this seems to cause windows to load a little slower but nothing too serious.

P.s. I think this tends to happen more often when using killswitch, but I don’t think exclusively.

Just wondering.

Kind regards,