Seaquel
SQL Server error code

SQL Server error 6511

SQL Server raises error 6511 at severity 16, which marks a problem with the query or data that you can correct.

Failed to initialize the Common Language Runtime (CLR) %ls with HRESULT 0x%x. You may fix the problem and try again later.
Msg6511
Severity16
Group6000–6999

Source: Database Engine events and errors