In some rare cases you may need to resend messages to OpenVista from Mirth after they have already been sent to OV. Once messages are received in OV, the Message Control ID (MSH-10) must be changed or OV will discard it as a duplicate.
For re-sending a few messages such as less than 10 you can manually update the MSH-10 and resend. For re-sending a bulk quantity of messages, you can prepend a 1 to the MSH-10 value through a transform.
You may apply a transform such as the following in the ADT send to OV: