SQL VDI error gets logged in OS event log even after a successful backup:
SQLVDI: Loc=IdentifySQLServer. Desc=MSSQL$(local). ErrorCode=(1060)The specified service does not exist as an installed service. Process=xxxx. Threads=xxxx. Client. Instance=(local). VD=.
The SQL Server backup itself has completed successfully.
However, this error being logged within Windows Event Viewer is an identified bug that has been fixed in version 5.6 and upwards of the SQL server plugin.