Disabled designer due to inheriting abstract class?

Question

I have a solution with one project. In that project are something live 40 or 50 forms. I've made 4 base forms that all the other forms can inherit. All 4 of those base forms inherit System.Windows.Forms.Form. Almost 90% of the forms inherit one of the first 2 base form. The rest inherits one of the last 2. But now I got this error out of nowhere, I made like 3 progs with the last 2 base forms and while I'm making the 5th, this errors occures and the designer is disabled.

The designer must create an instance of type 'xxxxxxx.frmBaseCr' but it cannot because the type is declared as abstract.

How an I solve this? I've searched on google for many hours now but I just can't find any working solution. I've tried the #if #else #endif statement but that doesn't seem to be working. I'm working in Visual Studio 2012 Express.

Answer 1

You need to remove the MustInherit keyword.