MyAssistant fails to send remittances for electronic payments

Hello,

The A/P department has informed me the remittances for electronic payments have not been sent in a couple of weeks (there's a task to run each week for it).

So far, I've tried/found the following:

1.  verified that the sending email address was correct and had the correct password

2.  checked the task in MyAssistant to ensure the criteria is correct

3.  checked the vendor email addresses to ensure they are correct

4.  i have found about four of seventy-eight notifications went out as i see their emails in our Office 365 queue

5.  i've checked the ISD database for errors and found many "the email directory "AP Vendor Contact 1" failed to resolve for task "Send vendors their electronic payment statement"

6.  the server's event logs show processID 7904 Failed to generate report 'AP Electronic Payment Notifications (ISD).rpt' with errors

One thing recently changed in the environment....

1.  Timberscan was upgraded to the latest version on March 6th, right before the remittances emails stopped working.  Not sure if that's a coincidence or not.