I have barracuda spam firewall 100 which sends/receives emails in our network. Off late i am seeing instances where the email delivery status shows as queued. there are two other situations where the message has expired.
However when i have tried to do telnet to these mail servers directly from my exchnage, the connection has been successful and the test mail went through with proper response from the recepient side server.
I am not sure how to troubleshoot it.
My exchange is 2007 with sp2. there are no errors or logs showing up on the servers indicating any trouble with it. barracuda support tells its a issue with isp , since they cant do tracert to any of the mail servers and it gets stopped at the isp ip. doing telnet from barracuda by going to advanced, troubleshooting tab, doesnt take me anywhere. it just hangs there.
want to check what really could be the problem before this becomes a bigger trouble. inbound emails are comign through fine without any issues.
my firewall is set to allow outbound any. havent sent any restrictions on the outbound traffic.