during migrating of well running website from one server to another server some times create common issues. this can be avoid by keeping some issues in mind.
common issues are like.
(1) Page not found Error on each request.
(2)Only .html are served not .aspx pages.
(3)URL rewriting not working.
(4) Loop of Request..
one of the following may be the cause of these issues.
(1) Ensure proper version of .Net framework is set or not from IIS.
(2) Ensure that All Extensions are mapped in configuration section of IIS.
(3) Ensure that Proper Wild card is inserted in Configuration section of IIS.
-This may be issue if you have used URL-Rewriting.
(4) Make sure that you have use all Extension as per type of platform of server(32-bit/64-bit)
-if you have 64-bit you have to mapped .dll from Framework64 directory.
(5) Check that you haven't use IP address of old server in your Code.
(6) Host headers are not configured properly.
-Loop of request may occur if you have configured Host headers incorrectly.