Error: 18453, Severity: 10, Login succeeded for user ‘%.*ls’. Connection made using Windows authentication.%.*ls
Error: 18454, Severity: 10, Login succeeded for user ‘%.*ls’. Connection made using SQL Server authentication.%.*ls
Error: 18455, Severity: 10, Login succeeded for user ‘%.*ls’.%.*ls
Error: 18456, Severity: 14, Login failed for user ‘%.*ls’.%.*ls%.*ls
Error: 18458, Severity: 14, Login failed. The number of simultaneous users already equals the %d registered licenses for this server. To increase the maximum number of

simultaneous users, obtain additional licenses and then register them through the Licensing item in Control Panel.%
Error: 18459, Severity: 14, Login failed. The workstation licensing limit for SQL Server access has already been reached.%.*ls
Error: 18460, Severity: 14, Login failed. The number of simultaneous users has already reached the limit of %d licenses for this ‘%ls’ server. Additional licenses should be obtained and installed or you should upgrade to a full version.%.*ls
Error: 18461, Severity: 14, Login failed for user ‘%.*ls’. Reason: Server is in single user

mode. Only one administrator can connect at this time.%.*ls
Error: 18462, Severity: 14, The login failed for user “%.*ls”. The password change failed. The password for the user is too recent to change. %.*ls
Error: 18463, Severity: 14, The login failed for user “%.*ls”. The password change failed. The password cannot be used at this time. %.*ls
Error: 18464, Severity: 14, Login failed for user ‘%.*ls’. Reason: Password change failed. The password does not meet Windows policy requirements because it is too short.%.*ls
Error: 18465, Severity: 14, Login failed for user ‘%.*ls’. Reason: Password change failed. The password does not meet Windows policy requirements because it is too long.%.*ls
Error: 18466, Severity: 14, Login failed for user ‘%.*ls’. Reason: Password change failed. The password does not meet Windows policy requirements because it is not complex enough.%.*ls
Error: 18467, Severity: 14, The login failed for user “%.*ls”. The password change failed. The password does not meet the requirements of the password filter DLL. %.*ls
Error: 18468, Severity: 14, The login failed for user “%.*ls”. The password change failed. An unexpected error occurred during password validation. %.*ls
Error: 18469, Severity: 10, [CLIENT: %.*hs]
Error: 18470, Severity: 14, Login failed for user ‘%.*ls’. Reason: The account is disabled.%.*ls
Error: 18471, Severity: 14, The login failed for user “%.*ls”. The password change failed. The user does not have permission to change the password. %.*ls
Error: 18482, Severity: 16, Could not connect to server ‘%.*ls’ because ‘%.*ls’ is not defined as a remote server. Verify that you have specified the correct server name. %.*ls.
Error: 18483, Severity: 16, Could not connect to server ‘%.*ls’ because ‘%.*ls’ is not defined as a remote login at the server. Verify that you have specified the correct login name. %.*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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