This is probably an easy answer but I'm new to Cisco and I have a Cisco 871.
If I try to check my email using the WAN address from the internal network I get an error that it can't connect. I enter the LAN address where the email server is located internally on our network and it works fine.
The reason I'm asking is I have a laptop and travel and don't want to constantly change my IP address, when I leave the building and when I return.
The WAN address works fine when I'm outside of our building. It doesn't work when I'm directly connected to the LAN.
Hope this isn't too confusing. Thanks in advance. I'm using SDM 2.2
I presume you are using NAT. When using NAT, the default config does not allow you to access a server using the public address from inside the internal LAN. There are workarounds to this problem (by doing NAT on a stick) but it's probably more hassle than it's worth....