I'm currently working on a project where a lot of initial migrating from ASP.NET 1.1 is needed. Usually the migration wizard in VS.NET 2005 takes care of things, but after converting the web sites, I realized that no ASP.NET 2.0-style partial classes where created for the web pages. Whenever I created a control i the markup, the usual magic of establishing af corresponding class instance in the .designer.cs did not occur. In fact, the .designer.cs file was not there.
The solution is quite simple - right click on the Web Application root and select Convert to Web Application. Now the .designer.cs files are added for each .aspx file in the project. Nice. Thanks to Ken Casada for a
detailed post on the subject.