You can add a message box to a macro. I am not sure how you would allow the message box to stop the printing though. I use VBA. You can print a report using VBA. Here is a snippit I sometimes use when I am creating many msgboxes in a form's module. It is not perfect in that it is not all on one line but, I like it for convenience of manipulating it for any situation.
Code:
Dim Msg, Style, Title, Response
Msg = " There was a problem scanning. " & vbCrLf
Msg = Msg + " Do you want to try again? " & vbCrLf
Msg = Msg + " Click No to save the white " & vbCrLf
Msg = Msg + " background as part of the file. "
Style = vbYesNo + vbInformation + vbDefaultButton1 ' Define buttons.
Title = "Bad Copy" ' Define title.
Response = MsgBox(Msg, Style, Title)
Select Case Response
Case vbYes ' User chose Yes.
Call DIB_Free(lngHdib)
Call TWAIN_CloseSource
Call TWAIN_EndMultipageFile
GoTo Scan_Now
Case vbNo
MsgBox "Your image will be saved now. "
GoTo Process_Now
End Select