OK, dumb question here I'm sure... I am getting errors trying to use standard dnn controls so...
just created a new module under /DesktopModules/TestModule. All references are correct. Using DNN 6.0.0

Want to add the texteditor to my Edit control with this:
<%@ Register TagPrefix="dnn" TagName="texteditor" Src="~/controls/texteditor.ascx" %>

and then:
<dnn:texteditor id="teContent" runat="server" height="200" width="500" />

BUT, the markup is showing an error: File ="~/controls/texteditor.ascx" was not found

AND, looking in the .designer.cs file I see:
protected global::System.Web.UI.UserControl teContent;

and not:
protected global::DotNetNuke.UI.UserControls.TextEditor teContent;

Just for testing, I manually edit the designer.cs file to be what it ought to be.

The strange workaround is: IF I have the .designer.cs file open in VS, the correct entry for the TextEditor remains (and the controls works in DNN) BUT, if I close the designer, the entry IN the designer reverts back to:  protected global::System.Web.UI.UserControl teContent; and I get all the errors again.

However, ALWAYS getting the errors in markup, no matter what.

Can ANYONE please tell me what might be wrong? Strange (at least to me).

Thanks

Thanks Cathal, and for the link!