Error: 3994, Severity: 16, User defined routine, trigger or aggregate tried to rollback a transaction that is not started in that CLR level. An exception will be thrown to prevent execution of rest of the user defined routine, trigger or aggregate.
Error: 3995, Severity: 16, Unknown transaction isolation level %d, valid value range is 0 to 5.
Error: 3996, Severity: 16, Snapshot isolation level is not supported for distributed transaction. Use another isolation level or do not use distributed transaction.
Error: 3997, Severity: 16, A transaction that was started in a MARS batch is still active at the end of the batch. The transaction is rolled back.
Error: 3998, Severity: 16, Uncommittable transaction is detected at the end of the batch. The transaction is rolled back.

Error: 3999, Severity: 17, Failed to flush the commit table to disk in dbid %d due to error %d. Check the errorlog for more information.
Error: 4001, Severity: 10, Client sends a sp_reset_connection while there is still pending requests, server is disconnecting.
Error: 4002, Severity: 16, The incoming tabular data stream (TDS) protocol stream is incorrect. The stream ended unexpectedly.
Error: 4004, Severity: 16, Unicode data in a Unicode-only collation or ntext data cannot be sent to clients using DB-Library (such as ISQL) or ODBC version 3.7 or earlier.
Error: 4005, Severity: 16, Cannot update columns from more than one underlying table in a single update call.
Error: 4006, Severity: 16, You cannot delete rows from more than one underlying table in a single delete call.

Error: 4007, Severity: 16, Cannot update or insert column “%.*ls”. It may be an expression.
Error: 4008, Severity: 16, The data types varchar(max), nvarchar(max), varbinary(max), and XML cannot be used in the compute clause by client driver versions earlier than SQL Server 2005. Please resubmit the query using a more recent client driver.
Error: 4009, Severity: 16, The incoming tabular data stream (TDS) protocol stream is incorrect. The TDS headers contained errors.
Error: 4010, Severity: 16, The incoming tabular data stream (TDS) protocol stream is incorrect. The Query Notification TDS header contained errors.
Error: 4011, Severity: 16, The incoming tabular data stream (TDS) protocol stream is incorrect. The MARS TDS header contained errors.
Error: 4012, Severity: 16, An invalid tabular data stream (TDS) collation was encountered.
Error: 4013, Severity: 16, The incoming tabular data stream (TDS) protocol stream is incorrect. The multiple active result sets (MARS) TDS header is missing.
Error: 4014, Severity: 20, A fatal error occurred while reading the input stream from the network. The session will be terminated (input error: %d, output error: %d).
Error: 4015, Severity: 16, Language requested in login ‘%.*ls’ is not an official name on this SQL Server. Using server-wide default %.*ls instead.

This is applicable on below versions of SQL Server

SQL Server 2005
SQL Server 2008 R2
SQL Server 2012
SQL Server 2014

Hope this was helpful.

Thanks,
SQLServerF1 Team
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