>I have the following scenario:
>I have a form (lets say Form1) where users can fill in the name, firstname... of a person. To check, if this person already exists, I want to start another form (lets say Form2) and display the "double" persons. I do this with a button in Form1 and the following click-event:

Christian,

Before going to deep with this, I feel there is an interface problem. Personnally I'd do the reverse thing. Sould'nt it be easier to set up an incremental combo box that would do the search and then, and only if there is no such customer, allow the user to add one.

You could design a single customer object and reuse it for "on the fly" customer creation (this case) and also on your customer maintenance form.

Other than that, your immediate problem has to see with DataEnvironments and data session. If you define private data sessions for your 2 forms and add a dataEnvironment to the second, you should be fine.

José