SQL Server – How to Stop Logging Messages in Error Log

I had a similar issue, not sure it will sort yours.

Try this:

EXEC master..sp_altermessage 1205, 'WITH_LOG', TRUE;
GO

Even though it was logging in the event log via the trace flag, this also needs to set in order to trigger the emails. You can see the table here:

select * from master.sys.messages
where text like '%deadlock%'

You can have more details here

Seems like you have an activation procedure that explicitly outputs the string y (probably using print but possibly raiserror, select, or output).

Why don't you change the procedure so that it doesn't have any output? Output shouldn't be needed when run through service broker. Or if the procedure is also sometimes run interactively, and output is required in that case, you could require a param for output (or create a wrapper procedure and call that instead).

There is no trace flag to suppress activation procedure output from the error log. This was a design decision to assist in troubleshooting activation procedures (since they are not typically run interactively).