MS SBS Exchange cannot send email

I have Small Business Server w/Exchange.

We had a power outage, came back on line, and everything is working except e-mail.

We are receiving e-mail from outside the network and can browse the Internet, but we cannot send e-mail outside the LAN.

Where do I start to look for the problem?

Does this sound like an ISP problem?

 

Do you have their permision to run a mail server. Many ISPs will block the mail ports if they find a server running.

 

Yes. The ISP hosts the domain and they deny any problem on their end.

 

Check your event log and your mail services. I bet there is a problem with the Internet Mail Connector service being stopped. The server or network connection went down and corrupted the IMCData folder. There are instructions on how to remedy this on the MS Knowledge base and updating to SP3 or higher will keep it from happening in the future

 

Apparently, the ISP just started bouncing outbound mail sent to mail.isp.com; so changing the outbound routing to DNS look up resolved the problem.

Unfortunately, they did not notify their customers before hand about the settings change.

Thanks for your help!