Please find a screen capture of CSIO's notification that they have made and update:

Step 1)
Should you experience an issue doing EDI with a 'MyHandler caught' error, then please have your local technical support person download and install this update.
Click here to follow install file:

Step 2)
Verify that you are on Mastercom Version 9.8m or 9.8n .
On your EDI computer, go to the Windows Start button listing your programs, choose Mastercom and then Settings Main.
This screen will tell you what version you are using. 
If you are not on version 9.8m or 9.8n, then please use your phone to take a picture of this screen or grab a screenshot or write the details down. 
To start your Mastercom update, please click here and print/follow these instructions.

Creation Date : June 17/2019
Revised Date: June 17/2019