Error: 18338, Severity: 10, Reason: Unable to determine the database name from the specified file name.
Error: 18339, Severity: 10, Reason: Failed to open the database ‘%.*ls’ specified in the login properties.
Error: 18340, Severity: 10, Reason: Failed to store database name and collation. Check for previous errors.
Error: 18341, Severity: 10, . Reason: Current collation did not match the database’s collation during connection reset.
Error: 18342, Severity: 10, Reason: Failed to send an environment change notification to a log shipping partner node.

Error: 18343, Severity: 10, Reason: Failed to retrieve database name or map database to an item while revalidating the login on the connection.
Error: 18344, Severity: 10, Reason: Connection with a login which does not specify a share is not allowed while revalidating the login on the connection.
Error: 18345, Severity: 10, Reason: Failed to open the database ‘%.*ls’ configured in the login object while revalidating the login on the connection.
Error: 18346, Severity: 10, Reason: Failed to determine database name from a given file name while revalidating the login on the connection.
Error: 18347, Severity: 10, Reason: Failed to open the database ‘%.*ls’ specified in the login properties while revalidating the login on the connection.

Error: 18348, Severity: 10, Reason: Failed to store database name and collation while revalidating the login on the connection. Check for previous errors.
Error: 18349, Severity: 10, Reason: Current collation did not match the database’s collation during connection reset.
Error: 18350, Severity: 10, Reason: Failed to send an environment change notification to a log shipping partner node while revalidating the login.
Error: 18351, Severity: 10, Reason: Client impersonation failed.
Error: 18352, Severity: 10, Reason: Failed to revert impersonation to self.
Error: 18353, Severity: 10, Reason: Failed to get security token information.
Error: 18354, Severity: 10, Reason: Failed to duplicate of security token.
Error: 18355, Severity: 10, Reason: Failed attempted retry of a process token validation.
Error: 18356, Severity: 10, Reason: An error occurred while attempting to change password.
Error: 18357, Severity: 10, Reason: An attempt to login using SQL authentication failed. Server is configured for Windows authentication only.

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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