Yahoo is continuously deferring messages. Has anyone any experience of tuning ironports delivery parameters so that they work well with yahoo smtp servers.
Here is a good article that explains the problem
The typical message returned is
Remote host said: 421 Message from(xxx.xxx.xxx.xxx) temporarily deferred - 4.16.50. Please refer to http://help.yahoo.com/help/us/mail/defer/defer-06.html/
Any ideas / suggestions gratefully received