Job Message logs may contain the following:
MSSQL: error: backup of database 'XXX' on 'XXXXX' server instance failed unexpectedly: Could not load file or assembly 'Microsoft.SqlServer.BatchParser, Version=184.108.40.206, Culture=neutral, PublicKeyToken =89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified.
MSSQL: error: unexpected System.IO.FileNotFoundException exception while attempting backup: Could not load file or assembly 'Microsoft.SqlServer.Smo, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified.
SQL Backup tab within RvxConfig may also show:
Error enumerating sql databases: Could not load file or assembly 'Microsoft SqlServer.Smo, Version=220.127.116.11, Culture=neutral,
PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified.
The two documents on SQL Server compatibility covers this in detail (see attached). If the error indicates you're looking for version 10 the client version is newer than 18.104.22.168 and you'll want the SQLServerCompatibility2008 file. If the error indicates we're looking for version 9 (in the above example: Version=22.214.171.124), the client version is 126.96.36.199 or older and you'll want the SQLServerCompatibility file. The version of the SMOs that you need to install are based on the Backup Agent, not the version of SQL you are running. If the client you are running is 188.8.131.52 or later you will need to install the 2008 SMOs, if the client you have is earlier than 184.108.40.206 you will need the 2005 SMOs.
Please note that loading the 2005 SMOs (version 9) on a 2008 SQL Server is in no way downgrading. Also, while the 2008 entire pack is not compatible with a 2005 SQL server, the SMOs alone are compatible and should not cause any problems with the SQL Server.