Remember that in .NET, all forms are really objects.
If you want to set a property in an instance of some object, you have to have a reference to that object.
Same thing in this case - your frmChild needs a reference to frmMain before it can set a public property or call a public method on it. When you initially create frmChild, you'll need to pass it a copy of your frmMain's variable that you can then use later.
Chip H.
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