This is a symptom specifically when compiling an Excel VBA project. The following error occurs:
User-defined type not defin
My solution is not good news but at least it should work.
My case is: I have a .xlsm from a coworker. 1) I open it and click the button: it works fine. 2) I save the file, close excel, open the file again: now it doesn't work anymore. The conclusion is: the code is OK but excel can't manage references correctly. (I've tried removing the re-adding the references without any success)
So the solution is to declare every referenced object as Variant and use CreateObject("Foo.Bar") instead of New Foo.Bar.
For example:
Dim objXML As MSXML2.DOMDocument
Set objXML = New MSXML2.DOMDocument
Replaced by:
Dim objXML As Variant
Set objXML = CreateObject("MSXML2.DOMDocument")