I recently purchased a ASA 5505 to replace my Microsoft ISA server. As a test I set up MS Small business server as a test box to get familiar with configuring the ASA. The SBS has exchange server, DHCP and DNS all enabled. the DNS has forwarders pointing to my ISP DNS servers. My Client machines all point to the DNS server on the SBS Server. In the default configuration everything works fine and the client machine can access the internet without issue. Once I establish a static route to the server to publish the mail server, the clients can no longer resolve names outside of the local machines. I've tried may different configurations and ACL's and can't seem to get it to work. I was hoping that one of you might be able to point me in the right direction. Below is the show config that works (No Static route to the Mail server) and the Show config after I add the routes.
Upon Further Review, I didn't even need to set up the Nat and ACL for Port 53. So I removed it. Here's the running config. FYI I also mapped ports 80 and 443 to a different server 192.168.1.20. If you are using the SBS as your webserver for remote access you should map those over to 192.168.1.2
The first full static nat that you configured was binding the whole interface address to the SBS, so the clients could not get outside. I always use port redirection instead of full static nat in similar network cases.