Troubleshoot ISS Web app server and Cisco ASA Firewall .

We have a ISS Web app server that holds image files to be access by clients. Now when clients try to access images on the file server they get timed out trying to get to the link with image. The webserver had worked previously , until a switch went bad and was replaced .. but since that was replaced - we cant get image links to get served up by the website application server.

ISS Web app server running on WIndows 2003 Server.
Cisco ASA 5505 Firewall appliance.