Error: 18318, Severity: 10, Reason: Failed to unprotect memory containing sensitive information.
Error: 18319, Severity: 10, Reason: Simulation of a failure while redoing login on the connection.
Error: 18320, Severity: 10, Reason: SQL Server service is paused. Login could not be revalidated at this time.
Error: 18321, Severity: 10, Reason: Reinitialization of security context failed while revalidating the login on the connection.

Error: 18322, Severity: 10, Reason: Access to server validation failed while revalidating the login on the connection.
Error: 18323, Severity: 10, Reason: Failed to open the specified database while revalidating the login on the connection.
Error: 18324, Severity: 10, Reason: Failed to create the user instance while revalidating the login on the connection.
Error: 18325, Severity: 10, Reason: Failed to attach the specified database while revalidating the login on the connection.
Error: 18326, Severity: 10, Reason: Failed to open the database for this login while revalidating the login on the connection.

Error: 18327, Severity: 10, Reason: Failed to determine the language and date format while revalidating the login on the connection.
Error: 18328, Severity: 10, Reason: An exception was raised while revalidating the login on the connection. Check for previous errors.
Error: 18329, Severity: 10, Reason: Simulation of a failure while reauthenticating login.
Error: 18330, Severity: 10, Reason: SQL Server service is paused. Login cannot be reauthenticated at this time.
Error: 18331, Severity: 10, Reason: Failed to reinitialize security context while reauthenticating login.
Error: 18332, Severity: 10, Reason: Failed to access server for validation while reauthenticating login.
Error: 18333, Severity: 10, Reason: Failed to open the specified database while reauthenticating login.
Error: 18334, Severity: 10, Reason: An error occurred while reauthenticating login. Check for previous errors.
Error: 18335, Severity: 10, Reason: Could not retrieve database name or map database to an item.
Error: 18336, Severity: 10, Reason: Cannot connect with a login that does not specify a share.
Error: 18337, Severity: 10, Reason: Failed to open the explicitly specified database ‘%.*ls’.

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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