What is the difference between Server.Transfer and response.Redirect?
The difference between the Server.Transfer and the response.Redirect them are as follows:-
1)Response.Redirect send a message to the browser saying it to move to some other page, while server.transfer does not send any message to the browser but rather redirects user directly from the server itself. So in the server.transfer there is no round trip while in the response.redirect there is a round trip and hence puts a load on the server.
2) In the Using Server.Transfer you can't redirect to a different from the server itself. For e.g. if your server is www.yahoo.com you can use server.transfer to move to www.microsoft.com but you can yes move to www.yahoo.com/travels, i.e. within websites. This cross server redirect is only possible using Response.redirect.
3) With the server.transfer you can preserve your all information. It has a parameter known as "preserveForm". So the existing query string will be able to call a page. In response.redirect you can maintain the state, but has lots of demerits.