I have 30+ voicemails that were sent to the Unity MTA/Failed folder over the last month due to the fact that the associated Exchange account was somehow deleted - I have since recreated the exchange account and the voicemail box is now working properly again but Unity is still holding on to the old messages in the failed folder. Is there a way I can "force" Unity to resend these messages from the failed folder? Usually Unity sees that the mailbox is accessible again and resends the messages in the failed folder, but i think since the issue is over 30 days old it has stopped trying.
You sure can. Cut those messages and paste them back into UnityMTA(making sure you have both .txt and .wav coupled together for each message). Unity won't check the Failed folder, once delivered to Failed, they have to be manually moved up a directory for Unity to pick up on them.
Hope that helps,