Seaquel
SQL Server error code

SQL Server error 1931

SQL Server raises error 1931 at severity 16, which marks a problem with the query or data that you can correct.

The SQL statement cannot be executed because filegroup '%.*ls' is offline. Use the sys.database_files or sys.master_files catalog view to determine the state of the files in this filegroup and then restore the offline file(s) from backup.
Msg1931
Severity16
Group1000–1999

Source: Database Engine events and errors