Our SBS server has been acting weird on the Exchange side of things for a few days now.
One particular problem is that certain emails with attachments are being blocked. These attachments are other emails (.msg files I assume). Now this Has never been a problem before as far as I know.
The emails are getting stuck in the SMTP connector queue and the error message at the bottom of the screen is:
'Unable to open the message for delivery'
I've increased diagnostic logging for MSExchageTransport, checked the resulting NDR (which just returns a 4.4.7 error which is no use). I've check messaage tracking for the messages, and nothing is here - it just shows "SMTP: Message Routed and Queued for Remote Delivery"
Any ideas anyone why this would suddenly start happening?
Not sure if this is related or not, but I'm also experiencing the following problem at the moment : http://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/Q_24568181.html
Thanks in advance for any help...