Error: 35234, Severity: 16, Database name ‘%ls’ was specified more than once. Reenter the command, specifying each database name only once.

Error: 35235, Severity: 16, The system name ‘%ls’ was specified more than once in the REPLICA ON clause of this command. Reenter the command, specifying a different instance of SQL Server for each replica.
Error: 35236, Severity: 15, The endpoint URL was not specified for the availability replica hosted by server instance ‘%.*ls’. Reenter the command, specifying the endpoint URL of this instance of SQL Server.
Error: 35237, Severity: 16, None of the specified replicas for availability group %.*ls maps to the instance of SQL Server to which you are connected. Reenter the command, specifying this server instance to host one of the replicas. This replica will be the initial primary replica.

Error: 35238, Severity: 16, Database ‘%.*ls’ cannot be added to availability group ‘%.*ls’. The database does not exist on this SQL Server instance. Verify that the database name is correct, then retry the operation.
Error: 35239, Severity: 16, The ALTER DATABASE SET HADR SUSPEND (or SET HADR RESUME) statement failed on database ‘%.*ls’ of availability group ‘%.*ls”. Either the availability group does not contain the specified database, or the database has not joined the availab
Error: 35240, Severity: 16, Database ‘%.*ls’ cannot be joined to or unjoined from availability group ‘%.*ls’. This operation is not supported on the primary replica of the availability group.
Error: 35242, Severity: 16, Cannot complete this ALTER DATABASE SET HADR operation on database ‘%.*ls’. The database is not joined to an availability group. After the database has joined the availability group, retry the command.
Error: 35243, Severity: 16, Failed to set resource property ‘%.*ls’ for availability group ‘%.*ls’. The operation encountered SQL Server error %d. When the cause of the error has been resolved, retry the ALTER AVAILABILITY GROUP command later.

Error: 35244, Severity: 16, Database ‘%.*ls’ cannot be added to availability group ‘%.*ls’. The database is currently joined to another availability group. Verify that the database name is correct and that the database is not joined to an availability group, then retry the operati

Error: 35246, Severity: 16, Failed to create the availability group. A SQL Server instance name could not be validated because the dynamic link library (DLL) file ‘%ls’ could not be located (Windows System Error %d). Verify that the specified server instance exists. If it exists, th
Error: 35247, Severity: 16, Failed to create the availability group. A SQL Server instance name could not be validated because the dynamic link library (DLL) file ‘%ls’ could not be loaded (Windows System Error %d).
Error: 35249, Severity: 16, An attempt to add or join a system database, ‘%.*ls’, to an availability group failed. Specify only user databases for this operation.
Error: 35250, Severity: 16, The connection to the primary replica is not active. The command cannot be processed.
Error: 35251, Severity: 16, This command can be run only on the primary replica. Connect to the primary replica, and retry the command.
Error: 35252, Severity: 16, The command can only be run on a secondary database. Connect to the correct secondary replica, and retry the command.
Error: 35253, Severity: 16, Database “%.*ls” is not in the correct state to become the primary database. The log must be restored from the previous primary replica to bring the database out of out of the reinitializing state.
Error: 35254, Severity: 16, An error occurred while accessing the availability group metadata. Remove this database or replica from the availability group, and reconfigure the availability group to add the database or replica again. For more information, see the ALTER AVAILABILITY G
Error: 35255, Severity: 16, An attempt to start database ‘%.*ls’ failed because the database is already started and online.
Error: 35256, Severity: 16, The session timeout value was exceeded while waiting for a response from the other availability replica in the session. That replica or the network might be down, or the command might be misconfigured. If the partner is running and visible over the networ

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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