Hi loftty,
Have you set the ContextMenuStrip property of your child form already? Did you just drag a ContextMenuStrip form the ToolBox of Visual Studio and drop it on the form?
Please see the ContextMenuStrip property of your child form, if it is none, you need to set it by the DropDowList.
If the problem is not I have thought, please feel free to tell me.
Sincerely,
Kira Qian
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