>I have this code:
>
>

                mmAppWPF.WindowManager.Show(new OutboundInvoiceReportViewer(invoicePKs), this);
>
>                MessageBoxResult result = mmAppWPF.MessageBox.Show("Did all Invoices print successfully?",
>                                       "Invoice Print",
>                                       MessageBoxButton.YesNo,
>                                       MessageBoxImage.Question);

>
>Which displays the messagebox before the report has been displayed fully (just the outline of the form with the report viewer in it gets displayed).
>
>This looks exactly like this code:
>
>

                mmAppWPF.WindowManager.ShowDialog(new InvoiceWithDetailReportViewer(manifestNumbers), this);
>
>                MessageBoxResult result = mmAppWPF.MessageBox.Show("Did all Invoices print successfully?",
>                   "Invoice Print",
>                   MessageBoxButton.YesNo,
>                   MessageBoxImage.Question);

>
>which displays the form with the report viewer properly, then when I close the form the messagebox gets displayed. This is how I want it to work. Does anyone have any idea why the first set of code might work differently?

I see one difference:
Try to change

 mmAppWPF.WindowManager.Show(new OutboundInvoiceReportViewer(invoicePKs), this);
// to
 mmAppWPF.WindowManager.ShowDialog(new OutboundInvoiceReportViewer(invoicePKs), this);