This is a good example of why you should use form classes.
Have your parent form class 'frmParentForm' and have a method called SetTextBox() on it which takes a string. Also have your button to launch your child form.
SetTextbox() code:
lparameters lcString thisform.textbox1.value = lcString
Your child form class 'frmChildForm' has a property 'CallingForm' and a method called Setup()
So in your code:
loParentForm = CreateObject("frmParentForm") loParentForm.Show()
In your parent form 'launch child form' button:
loChildForm = CreateObject("frmChildForm") loChildForm.Setup(this) loChildForm.Show()
In your child form Setup() method:
lparameter loCallingForm This.CallingForm = loCallingForm
So now your child form has a reference back to the form that called it. So on your child form you can now do:
thisform.CallingForm.SetTextbox("hello")