RefEdit is a standard Forms control, not an ActiveX control.
Much has been written about using the RefEdit control, and a Google search for "excel vba refedit" (without the quotes) will yield items reporting problems with using it.
Jon Peltier has a useful web page, Using RefEdit Controls in Excel Dialogs, at
http://peltiertech.com/WordPress/using-refedit-controls-in-excel-dialogs/
When I write Excel VBA on Windows (and subsequently test on the Mac), before I create an add-in, I now follow his advice: "To reduce the risk of RefEdit-related issues, you should uncheck the box in front of Ref Edit Control in the References dialog."
So, the original poster might be able to solve the problem by unchecking the Ref Edit Control reference and clicking OK.
- Mike Middleton, www.TreePlan.com