Does .net 1.1 support 64 bit OS?

Question

If so are the changes I would need to make to an existing program written in c# vast?

Answer 1

This MSDN page has more information on 64 bit Applications:

All applications built with the 1.0 and 1.1 releases of the .NET Framework are treated as 32-bit applications and are always executed under WOW64 on the 32-bit common language runtime (CLR) on a 64-bit operating system. In addition, 32-bit specific applications built with version 2.0 of the .NET Framework would run under WOW64 on 64-bit platforms.

So you need .NET 2.0 to be able to target 64 bit specifically.

Answer 2

This link might provide some pointers assuming it is Visual studio 2003 you are referring to:

http://www.toymaker.info/Games/html/64_bit.html

Answer 3

Visual Studio 2003 only targets the 32 bit platform, so you would need a newer version to create an application that can run in 64 bit mode.

Normally you don't have to make any code changes at all to make an application compatible with the 64 bit platform. I have done a lot of development and testing on a 32 bit computer and published on a 64 bit web server, and also the opposite.