I try to create backup via Power Panel New backup > Backup Start > New Task.
However it fails with error:
Application Error The server has encountered an internal error or misconfiguration. Contact your support representative. Please report this problem to the technical support.
Manually backup works correctly.
There is misconfiguration of Power Panel, Backup Start > New Task should exist in PVA Only.
Re-install PVA agent to the current version with help of the following article: #113071