Failed Logins Attempts Detected
This warning has been raised because the server error log has found one or more failed database logins. Although they may be benign, such as DBA mistyping a password, they may also be a result of an attempt to gain unauthorized access to the database.
Investigate the login failures.
How to Scan the SQL Server Error Log for Failed Logins
DECLARE @SearchText NVARCHAR(40) = 'login failed'; EXEC master.dbo.xp_readerrorlog 0, 1, @SearchText, NULL, NULL, NULL;;
MSSQLSERVER_18456 | Microsoft Docs