Filip,

>I get a compile error on the line
>

this.MdiParent = App.MainForm;

>Error message is :
>

The type or namespace name 'App' could not be found (are you missing a using directive or an assembly reference?)

As Jason suggested, it sounds like you need to add a reference to the appropriate namespace. There are a few ways to get at this main form reference. If you use the mmAppDesktop class (note the "mm" prefix), you would do it as follows:

OakLeaf.MM.Main.Windows.Forms.mmAppDesktop.MainForm;

Regards,