Arg....
1) that code shouldn't be in the form load event of frmMain
2) that code shouldn't be in the form load event of the child form
3) you missed the most important piece of code... how in blue blazes are you showing the form? Specifically the menu click events? If that's where you're showing your forms, THAT's what we need to see... In THEORY it should be something like this:
Code:
Dim newUser as New frmNewUSer
newUser.MDIParent = Me
newUser.Show
That's it.. nothing complicated... create a new instance of the form... set the mdi parent, and show it... baddum-boom-badda-bing

"The child forms are mostly opened by the user clicking on menu items"
MOSTLY? what about the rest of the times? What ever... should be the same as the menu click events... in fact if that is the case and you are showing the form from different places, wrap it in a sub and call the sub from where you need to.

-tg