851 router with mailserver behind it

[christopherwilliams]

Hi,

Bit of a beginers question, first time weve used a cisco in the office. We have replaced a netgear router with a 851W for reliability reasons. I have it all working as planned except for our mailserver, users behind the router cant access the mailserver (except by changing mail client to its local IP, which then doesnt work from outside the office) our other offices can pick up and send mail. DNS is assigned by the ISP via router. I think i need to do something to forward POP3 and SMTP to the mail server rather than trying to go out and in again. I have managed to forward ports for incoming, hence the other offices working, but cannot work out how to do it this side of the router. Strangely we never had this issue with the netgear. By the way, if anyone knows how to do this using SMD rather than command line that would be much appreciated (real beginer)

[rais.ahmad]

How about using DNS inside to map mailserver to internal IP.

Hope that helps.

[christopherwilliams]

Thanks for the response,

Do you mean run a DNS server on a machine on network? Had thought of that but as its only a workgroup not a domain, didnt realy want to do this. Strange thing is the suposedly inferior Netgear router had no problems with this at all. If possible I would like an 'on router' solution as there are a lot of laptops that come and go, and they need to work from a variety of external sites, which they do OK, just cant use them in the office with the router without changing the settings from default. Any thoughts? thanks in advance