Error: 3954, Severity: 16, Snapshot isolation transaction failed to start in database ‘%.*ls’ because the ALTER DATABASE command that disallows snapshot isolation had started before this transaction began. The database is in transition to OFF state. You will either need to change t
Error: 3955, Severity: 16, Snapshot isolation transaction failed in database ‘%.*ls’ because the recovery was skipped for this database. You must recover the database before you can run a transaction under snapshot isolation.
Error: 3956, Severity: 16, Snapshot isolation transaction failed to start in database ‘%.*ls’ because the ALTER DATABASE command which enables snapshot isolation for this database has not finished yet. The database is in transition to pending ON state. You must wait until the ALTER

Error: 3957, Severity: 16, Snapshot isolation transaction failed in database ‘%.*ls’ because the database did not allow snapshot isolation when the current transaction started. It may help to retry the transaction.
Error: 3958, Severity: 16, Transaction aborted when accessing versioned row in table ‘%.*ls’ in database ‘%.*ls’. Requested versioned row was not found. Your tempdb is probably out of space. Please refer to BOL on how to configure tempdb for versioning.
Error: 3959, Severity: 10, Version store is full. New version(s) could not be added. A transaction that needs to access the version store may be rolled back. Please refer to BOL on how to configure tempdb for versioning.
Error: 3960, Severity: 16, Snapshot isolation transaction aborted due to update conflict. You cannot use snapshot isolation to access table ‘%.*ls’ directly or indirectly in database ‘%.*ls’ to update, delete, or insert the row that has been modified or deleted by another transacti

Error: 3961, Severity: 16, Snapshot isolation transaction failed in database ‘%.*ls’ because the object accessed by the statement has been modified by a DDL statement in another concurrent transaction since the start of this transaction. It is disallowed because the metadata is no
Error: 3962, Severity: 16, Bind to another transaction while executing SQL Server internal query is not supported. Check your logon trigger definition and remove any sp_bindsession usage if any. If this error is not happening during logon trigger execution, contact production suppo
Error: 3963, Severity: 16, Transaction failed in database ‘%.*ls’ because distributed transactions are not supported under snapshot isolation.
Error: 3964, Severity: 16, Transaction failed because this DDL statement is not allowed inside a snapshot isolation transaction. Since metadata is not versioned, a metadata change can lead to inconsistency if mixed within snapshot isolation.
Error: 3965, Severity: 16, The PROMOTE TRANSACTION request failed because there is no local transaction active.
Error: 3966, Severity: 17, Transaction is rolled back when accessing version store. It was earlier marked as victim when the version store was shrunk due to insufficient space in tempdb. This transaction was marked as a victim earlier because it may need the row version(s) that hav
Error: 3967, Severity: 17, Insufficient space in tempdb to hold row versions. Need to shrink the version store to free up some space in tempdb. Transaction (id=%I64d xsn=%I64d spid=%d elapsed_time=%d) has been marked as victim and it will be rolled back if it accesses the version
Error: 3968, Severity: 10, Snapshot isolation or read committed snapshot is not available in database ‘%.*ls’ because SQL Server was started with one or more undocumented trace flags that prevent enabling database for versioning. Transaction started with snapshot isolation will fai
Error: 3969, Severity: 16, Distributed transaction is not supported while running SQL Server internal query. Check your logon trigger definition and remove any distributed transaction usage if any. If this error is not happening during logon trigger execution, contact production su
Error: 3970, Severity: 16, This operation conflicts with another pending operation on this transaction. The operation failed.
Error: 3971, Severity: 16, The server failed to resume the transaction. Desc:%I64x.
Error: 3972, Severity: 20, Incoming Tabular Data Stream (TDS) protocol is incorrect. Transaction Manager event has wrong length. Event type: %d. Expected length: %d. Actual length: %d.
Error: 3973, Severity: 16, The database is currently being used by another thread under the same workspace in exclusive mode. The operation failed.

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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