Firewall rule help

[Ish]

Hi

I set these outgoing rules in our firewall:-

ALLOW ALL USERS PORT 53(DNS) WAN 208.67.220.220
ALLOW ALL USERS PORT 53(DNS) WAN 208.67.200.200
BLOCK ALL USERS PORT 53(DNS)

This had the desired effect of only allowing people internet access using the www.opendns.com DNS servers.

The problem I had is that it no one was getting any emails from the exchange server. As soon as I took the rules off all emails came through.

What do I need to change to allow the emails to work?

Thanks

 

[Peace]

have you checked what dns servers are set on the exchange server ?

 

[Ish]

I've allowed the exchange server outbound access to any DNS service and it's working fine now. Thanks.