Tim Maxey .NET Technology Blog & Resources
I had an ANNOYING problem with Visual Studio 2008 and the AjaxControlToolkit.dll. Seemed like if I had an Update Panel on the aspx age, I would get asked if I wanted to replace the AjaxControlToolkit.dll. ANNNOYING, so I did some searching and finally did this:
1. In VS 2008 I had to right click on the toolbar and choose the option "choose items," then I sorted the the .NET Framework Components and unchecked the AjaxControlToolkit version version 3.0.1xxx and keep the 3.0.2xxx.
2. Next I went to the property page of the project and references and removed the AjaxControlToolkit reference, then I went to my aspx page and re-added the ToolKitScriptManager back to the page.
That did it!