Symptoms

Backup fails with the following error:

The snapshot creation has failed due to a hardware issue or a conflict with your disk hardware. Windows has reported the following error: 'The device, \Device\X, has a bad block.'.

Example of full error log: click to expand

 

Error code: 50305
Module: 16
LineInfo: 0x3FEC04E376B89F0A
Fields: {"$module":"disk_bundle_vsa64_12960"}
Message: Failed to read the snapshot. To troubleshoot VSS issues, download and run Acronis VSS Doctor available at https://www.acronis.com/en-us/personal/vss-diagnostic-free-tool/
------------------------
Error code: 341
Module: 16
LineInfo: 0x02AACB7B2AB852AF
Fields: {"$module":"disk_bundle_vsa64_12960"}
Message: CRC error.
------------------------
Error code: 1537
Module: 149
LineInfo: 0x3FFB3FF75C471B29
Fields: {"$module":"disk_bundle_vsa64_12960"}
Message: The device, \Device\Harddisk0\DR0, has a bad block.
------------------------
Error code: 1537
Module: 149
LineInfo: 0x3FFB3FF75C471B29
Fields: {"providerName":"disk","Computer":"Acronis.local","Channel":"System","$module":"disk_bundle_vsa64_12960","EventID":"7","providerGUID":"00000000-0000-0000-0000-000000000000"}
Message: The device, \Device\Harddisk0\DR0, has a bad block.

Cause

The most common reason is a physical error on the hard drive that you attempt to back up.

Another possible reason is high workload on the backed up drives at backup time.

Solution

1) Reschedule backup to a time when the I/O load is lower.

2) If backup still fails when workload is low, most likely cause of the issue is a physical error on the hard drive. Find the faulty disk using Windows Event Viewer and Acronis Disk Report (or a different utility for checking hard disk for errors).

• Review Windows event logs, see details in this article.
• Review Acronis Disk Report, as described below.

1. Download and run the Acronis System Report.
2. The tool's output is an archive with diagnostic information. Find the disk report within it and check if there are errors
   

   The C column stands for Full partition check status:

   C - means there are no errors
   E - means that an error was found
   W - means a warning

If Acronis Report shows E or W for the drive that you are trying to backup, or Windows Event logs show errors related to a certain disk/partition, then it is recommended to check the partition for errors and repair. You can Windows native Check Disk utility or diagnostic tools provided by your hardware manufacturer.

How to run Check Disk utility

1. Make sure that you have a healthy backup of the machine. If not, you can create one using Acronis Bootable Media (not applicable to Acronis Cyber Backup Cloud/Acronis Cyber Protect Cloud).
2. Launch elevated Command Prompt (Start -> run -> cmd - > right-click and select Run as Administrator) and enter following command:

   chkdsk <disk letter>: /r

   where <disk letter> is the partition letter you need to check, e.g. chkdsk D: /r

3. Note that checking the C: drive may require you to reboot the machine.

3) If errors and bad blocks remain after fixing the disk with Check Disk or hardware manufacturer's tools, consider replacing the faulty hardware.

If the disk shows no errors but the issue persist, please create a system report (see Acronis Cyber Protect Cloud: Collecting System Report, Acronis Cyber Backup 12.5 and 12: Collecting System Information) of the affected machine and contact Acronis Support with a reference to this article.