Failing backup

I have 1 backup that's constantly failing where as all my others are working fine. I've tried to delete the Task and recreate it but had no luck.
I'm running Acronis Backup for VMware 9.2.10535 on vCenter 5.5
The log is showing the following;
Task 'NEW_Core_Backup' failed: 'Failed to create a backup.
Additional info:
--------------------
Error code: 3
Module: 435
LineInfo: 555b5abba0950340
Fields:
Message: Failed to create a backup.
--------------------
Error code: 32786
Module: 114
LineInfo: 28314c961de7d337
Fields:
Message: Failed to prepare for backing up.
--------------------
Error code: 353
Module: 149
LineInfo: a71592046cb2c5f6
Fields:
Message: Failed to back up the group.
--------------------
Error code: 2
Module: 218
LineInfo: 338a407ad20e0987
Fields:
Message: Error occurred while running the backup and recovery engine.
--------------------
Error code: 1080
Module: 1
LineInfo: d1ab7fa1e56ec8bf
Fields:
Message:
--------------------
Error code: 13
Module: 149
LineInfo: d1ab7fa1e56eca4e
Fields:
Message: Failed to perform the requested operation.
--------------------
Error code: 103
Module: 83
LineInfo: a859dd78cc91df40
Fields:
Message: Failed to open the virtual machine ([VMFSDatastore4] STL-SP-VM/STL-SP-VM.vmx).
--------------------
Error code: 253
Module: 83
LineInfo: c7610e0a857bedf4
Fields:
Message: VMware error: 'Remote method call failed.'.
--------------------
Error code: 32
Module: 0
LineInfo: c7610e0a857bedf4
Fields:
Message: Awaiting task 'CreateSnapshot' has failed. Reason: An error occurred while saving the snapshot: Failed to quiesce the virtual machine..
--------------------'.
Any ideas what I can try? I've tried to update VMware tools also.

Thanks Vasily - this has resolved my issue.
Regards,
- Accedi per poter commentare
Best regards,
Vasily
Acronis Virtualization Program Manager
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