Cryptographic Services failed while processing the OnIdentity() call in the System Writer Object. AddLegacyDriverFiles: Unable to back up image of binary Microsoft Link-Layer Discovery Protocol. Access is denied.
System Writer and MSMQ Writer seem to get stuck in a "Waiting for completion". Resetting them does not resolve the issue
This is a known Microsoft issue of related to Event ID 513 when running VSS in Windows Server. The resolution is posted in Microsoft Help Article 3209092
Once completed, please run a new 1-Time Full (on demand) backup.
Unitrends uses the NT AUTHORITY\SERVICE (also known as the local SYSTEM account) to conduct the backups. However, when you review the Microsoft Event Viewer > Application logs, you find the following error:
AddLegacyDriverFiles: Unable to back up image of binary Microsoft Link-Layer Discovery Protocol.
Access is denied.