Error: 18485, Severity: 16, Could not connect to server ‘%.*ls’ because it is not configured to accept remote logins. Use the remote access configuration option to allow remote logins.%.*ls
Error: 18486, Severity: 14, Login failed for user ‘%.*ls’ because the account is currently locked out. The system administrator can unlock it. %.*ls
Error: 18487, Severity: 14, Login failed for user ‘%.*ls’. Reason: The password of the account has expired.%.*ls
Error: 18488, Severity: 14, Login failed for user ‘%.*ls’. Reason: The password of the account must be changed.%.*ls

Error: 18489, Severity: 10, The dedicated administrator connection is in use by “%.*ls” on “%.*ls”.%.*ls
Error: 18491, Severity: 16, SQL Server could not start because of an invalid serial number. The serial number information retrieved at startup appears invalid. To proceed, reinstall SQL Server.
Error: 18492, Severity: 16, SQL Server cannot start because the license agreement for this ‘%ls’ version of SQL Server is invalid. The server is exiting. To proceed, reinstall SQL Server with a valid license.
Error: 18493, Severity: 16, The user instance login flag is not supported on this version of SQL Server. The connection will be closed.%.*ls

Error: 18494, Severity: 16, The user instance login flag is not allowed when connecting to a user instance of SQL Server. The connection will be closed.%.*ls
Error: 18495, Severity: 16, The user instance login flag cannot be used along with an attach database file name. The connection will be closed.%.*ls
Error: 18496, Severity: 10, System Manufacturer: ‘%ls’, System Model: ‘%ls’.
Error: 18596, Severity: 16, %.*ls cannot start because your system is low on memory.
Error: 18597, Severity: 16, Your %.*ls installation is either corrupt or has been tampered with (%hs). Please uninstall then re-run setup to correct this problem
Error: 18598, Severity: 16, %.*ls could not find the default instance (%.*ls) – error %d. Please specify the name of an existing instance on the invocation of sqlservr.exe.\n\nIf you believe that your installation is corrupt or has been tampered with, uninstall then re-run setup to
Error: 18599, Severity: 16, %.*ls could not find the specified named instance (%.*ls) – error %d. Please specify the name of an existing instance on the invocation of sqlservr.exe.\n\nIf you believe that your installation is corrupt or has been tampered with, uninstall then re-run s
Error: 18750, Severity: 16, %ls: The parameter ‘%ls’ is not valid.
Error: 18751, Severity: 16, %ls procedure was called with the wrong number of parameters.
Error: 18752, Severity: 16, Only one Log Reader Agent or log-related procedure (sp_repldone, sp_replcmds, and sp_replshowcmds) can connect to a database at a time. If you executed a log-related procedure, drop the connection over which the procedure was executed or execute sp_replfl
Error: 18755, Severity: 16, Could not allocate memory for replication. Verify that SQL Server has sufficient memory for all operations.
Error: 18756, Severity: 16, Could not retrieve replication information for table %d. Verify that the table has a primary key, and then rerun the Log Reader Agent.

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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