Even if my English is really bad, I will try to expose the problem.
My operating system is Windows 10 20H2.
A few days ago, suddenly and without any modification on my part, one, and only one, of the tasks (complete and manually started) of Cobian Backup 11 Gravity no longer starts, it remains stuck at 0% and, in the end, created an (empty) file 1 KB in size. Specifically this is the task for the complete backup of the Mozilla Thunderbird profile (which has a weight of about 13 GB).
All other tasks run smoothly, including another one that handles nearly 19GB of data.
Without success, I tried:
- to recreate the task;
- to reset the permissions (as recommended in the FAQ), through "Tools - Reset permissions";
- to run a chkdsk of the disks, without encountering problems;
- to start the offending task from the Windows 10 safe mode;
- to change the backup destination folder;
- to disable the Volume Shadows Copy;
- to reinstall the program.
I even restored some old images of the operating system, to go back in time, but even in this case that particular task does not want to know to start.
Trying and trying, by pure chance, I changed the type of compression, from "Zip Compression" to "No Compression" or "7zip Compression".
Well, with "No compression" or "7zip compression" the task is executed!
It seems to me that it takes longer, however it is started and ended properly.
I investigated further and the problem would appear to come from the "C:\Users\user\AppData\Roaming\Thunderbird\Profiles\profilename\Mail\Feeds\" folder.
Under the "Feeds" folder I find other folders with messages from the RSS feeds inside. Some of these contain thousands of files. One, in particular, over 110 thousand files.
If I exclude these folders (at least those with more than 5 thousand files) using the specific functionality of the program, the task is executed! It takes a long time to start, but it starts up and proceeds as it should.
All this while maintaining the "Zip Compression".
At this point I ask: can the research I have done be considered correct? That is: is it right to conclude that in the presence of folders with thousands and even tens of thousands of files, if you want to use Cobian Backup, it is necessary to use "7zip compression" (or no compression)?
Thank you so much for your attention!