Visual Studio 2022 - ASP.net - Error Creating Control ajax Toolkit ... Page Design

Question

I have a Visual Studio 2022 ASP.net application that now displays "Error Creating Control ajax Toolkit" when viewing the Page Design:-

The application references the AjaxControlToolKit:-

And the path is pointing to the Ajax install path:-

The application builds and runs but when viewing the design page I get the "Error Creating Control" messages.

This seems to have started very recently.

Any ideas why?

tia

Answer 1

Just to add to my original question It appears that the "Web Live Preview" was the issue.

I set the option back to "Legacy Web Forms Designer" and it seems ok.

I found this similar post here