Thanks for your pointers, but the problem seems to be tough...

Appraently, the Dock Window command is designed to work ONLY between native VFP IDE window. In other words, apparrently, you can't programmatically dock user windows into IDE windows. However, I can manually do it. The help file says:

Docks an Integrated Development Environment (IDE) tool window or toolbar to the Visual FoxPro desktop window or another IDE window. There are two versions of the syntax. ... 

It does mention user-defined *toolbars*:

For a user-defined toolbar, you can use the Caption property as its name. If you specify an undockable window as the window to be docked, it becomes dockable internally

But, apparently not user defined windows (in my case it's an instance of a form class created by createobject)



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>See Re: COMMAND window: Docking/Text Display Question Thread #1179036 Message #1179054