When using a pre-1.6 MSSQL agent plugin the "mssql_blocked_sessions"
check plugins would crash during discovery.
The pre-1.6 MSSQL agent plugins are now deprecated and can no longer be used.
Old still existing services will go to "UNKNOWN" and encourage you to update to a newer agent plugin version.
After a rediscovery the old services will vanish and new services will not be discovered.
Therefore an upgrade as described in Werk #6140 is necessary.
To the list of all Werks