Seaquel
SQL Server error code

SQL Server error 6939

SQL Server raises error 6939 at severity 16, which marks a problem with the query or data that you can correct.

XML Validation: The element '%ls' is mixed content with a fixed value and therefore not allowed to have element content. %S_MSG %ls
Msg6939
Severity16
Group6000–6999

Source: Database Engine events and errors