<p>I am a .Net developer that has been tasked with upgrading a classic asp website to asp.net. The website is currently running on luck and bubble gum but there is not enough time or money to stop progress and do a full rewrite. Of course I will still need to be able to deliver new features while I am upgrading.</p>

<p>What strategies should I use to make a smooth gradual change to asp.net? Should I convert to a single tier .net solution and then refactor to a proper multi-tier solution or should I design my business and data layers now? Should I go straight to 3.5 or is it easier to just get to 1.1 and upgrade to 2.0 or 3.5 after?</p>

<p>A full conversion would probably take 3-5 months. There is also some existing 1.1 code, which is why I am considering using that as a jumping off point.</p>

How long would a complete conversion/rewrite take? It's also going to depend on how you've structured your original project.
I
can
answer that you should just target v2.0 (3.5 if you want/need it's features) from the beginning. There's no need to subject yourself to 1.1 of the framework.