A full volume backup does not work on a disk with a long shadow copy creation time

I have a problem with backing up one server (Windows Server 2008 R2 Datacenter, MySQL Server 5.0 and UrBackup Client 2.3.4.0). The server has two disks. On volume C: running system, database, and UrBackup Client. Volume D: contains only static data.

Full image backup of volume C: does not work, but backup of volume D: works correctly. I think that the problem is at the time of creation a volume shadow copy. On volume C: it takes a very long time (about 80 seconds), but on volume D: it is finished immediately.

I attach debug logs from UrBackup Client client.log (475.0 KB)
and from server (UrBackup Server 2.3.7) server.log (4.4 KB)

Could you give me an advice please? Thanks in advance.

It seems more likely that C: is e.g. nearly full and has no space for shadow copy data. This causes the shadow copy to be deleted straight after creation (causing the read errors in the log).
If you take a look at the event log on the client, you can get more information on why the shadow copy was deleted.

Thank you for the quick reply.
I checked the event log on the client and found the following error message:

15.3.2019 15:14:35 The shadow copies of volume C: they were aborted because the shadow copy storage could not grow due to a user-imposed limit.

Then I checked the shadow copy setting on drive C: and set No limit instead of the original maximum size (1024 MB).

I tried to run the backup again and I didn’t find the above error in the event log. Also errors:

ERROR: Reading XXXXXXXX failed. System error code 2

they no longer appeared.
But the backup still ends with the same error:

ERROR: Client disconnected before sending anything (Timeout: true).

I attach new debug logs: client.log (23.2 KB) server.log (1.9 KB)

Thank you for your time.

Could you reupload a new client.log after 2019-03-18 13:53:09 (with more than 1h more log data)?

Unfortunately, I stopped the UrBackup Client service at 12:54:36 so I don’t have any more log records.
But I did another test where I had the UrBackup Client running for about an hour.
I attach the new debug log: debug.log (53.6 KB)

P. S .: Sorry for garbling the error message in my previous post, it should be right:

ERROR: Reading from device at position XXXXXXXX failed. System error code 2

No more idea what’s going on… maybe you have something that kills idle connections after a few minutes…

What is the output of this?

vssadmin list shadowstorage

Windows defaults to 10GB. I use this command to increase to 50GB:

vssadmin resize shadowstorage /for=C: /on=C: /maxsize=50GB

Thank you very much for your answer.
As I wrote in one of my previous posts, I tried to set an unlimited size volume shadow copy, but the problem was not fixed:

C:\>vssadmin list shadowstorage
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line tool
(C) Copyright 2001-2005 Microsoft Corp.

Shadow Copy Storage association
   For volume: (\\?\Volume{1adc5435-14ff-11e5-8e01-806e6f6e6963}\)\\?\Volume{1adc5435-14ff-11e5-8e01-806e6f6e6963}\
   Shadow Copy Storage volume: (\\?\Volume{1adc5435-14ff-11e5-8e01-806e6f6e6963}\)\\?\Volume{1adc5435-14ff-11e5-8e01-806e6f6e6963}\
   Used Shadow Copy Storage space: 0 B (0%)
   Allocated Shadow Copy Storage space: 0 B (0%)
   Maximum Shadow Copy Storage space: 32 MB (32%)

Shadow Copy Storage association
   For volume: (D:)\\?\Volume{7bd5a440-304e-11e9-885b-005056a30028}\
   Shadow Copy Storage volume: (D:)\\?\Volume{7bd5a440-304e-11e9-885b-005056a30028}\
   Used Shadow Copy Storage space: 1.281 MB (0%)
   Allocated Shadow Copy Storage space: 320 MB (0%)
   Maximum Shadow Copy Storage space: 320 MB (0%)

Shadow Copy Storage association
   For volume: (C:)\\?\Volume{1adc5436-14ff-11e5-8e01-806e6f6e6963}\
   Shadow Copy Storage volume: (C:)\\?\Volume{1adc5436-14ff-11e5-8e01-806e6f6e6963}\
   Used Shadow Copy Storage space: 2.627 GB (2%)
   Allocated Shadow Copy Storage space: 4.461 GB (3%)
   Maximum Shadow Copy Storage space: UNBOUNDED (100%)

Earlier on this server full volume backups worked. In my opinion, backup stopped working after the time of creation volume shadow copy on C: exceeded about 60 sec.