Why did windows built-in backup stop working?

Question

Backup

For a long time, standard data archiving for backup of the entire system disk worked quite normally (OS - Windows 7). I recently installed Comodo Internet Security antivirus and everything was fine if the next scheduled backup did not end with an error:
0x81000037

Windows Backup was unable to read from the shadow copy on one of the volumes being backed up.

Having rummaged around the Internet, I found that everyone is referred to the same article on the Microsoft website, and specifically to the chapter with the heading "Problem 1 and Problem 2" and it says that you need to find and remove reparse points , which are not can be copied.
Everything would be fine, but the trouble is, all my reparse points are not those folders that can be deleted. These are the AppData, Cookies, Local , Roaming folders and the like, even the My Documents folder was on this list. Would you agree not to delete all this?
Another topic on the forum gave me the idea that it was Comodo's fault, where the girl got rid of the problemssimply deleting “some data” from one mounted folder that was quarantined by Comodo Internet Security antivirus , I could not repeat its experience, clearing the quarantine did not give anything, I don’t know if there were mounted folders among them , but I associate my troubles with this antivirus, because before it everything worked.
Any ideas what to do besides "change antivirus" and "don't use standard backups"?

Answer 1

While writing the question, I tried the "last idea" - and just by the time the writing was completed, the backup was successfully completed. Just in the archiving settings in the question: "What should be archived" answered "give a choice to Windows" .
Previously, I had the "Give me a choice" option selected and selected:
- all user library files
- the entire C partition
- the disk system image (C)
This differs from the choice of Windows only by one point - the entire C partition (Windows decided not to copy it) .
In general, everything seemed to work, but "light dissatisfaction" remained. The riddle has not yet been solved - what exactly prevented you from backing up the entire C drive.

Answer 2

The Microsoft article did not help me. I began to understand and it turned out that the shadow copy was not created on drive C.
It helped to increase the maximum disk space in the system protection settings.