Hi

We run SBS2011, since last friday for some reason all incoming mail is being rejected by exchange. The only thing that has been done is a Microsoft update. I can see the mail arriving at our Barracuda but is then rejected by exchange. we can still send mail out.

Hi ,

1.If the emails is being rejected by exchange then the sender might have received the NDR .Please share the NDR with us .

2.At the same time in barracuda device you could see the exact error message that could occur when the remote host (exchange) rejected the SMTP connection from Barracuda .

First thing I would check is disk space on the server. That can cause email to be rejected.

The NDR is important as already pointed out. That can give some clues. Look in the event viewer of the server as well for any indication of problems.

Simon.

Hi,

Do you have implemented inbound and outbound mail flow though Barracuda? Please check the relevant connector first, also ensure the Exchange service running well.

Also, please post NDR for further analyze as below mentioned.