"Error opening 'MHTestMessageProvider'" error occurs when testing messages in Portrait Dialogue 6.2

Product Feature: Dialogue Server - testing messages



PD 6.2 Error after upgrade

When trying to use test function for "Export as Text(all in one) Letter" in Visual Dialogue an error message appears.

Error opening 'MHTestMessageProvider': Could not convert variant of type (OleStr) into type (Boolean)


There was an issue which appeared in 6.2 and not fixed in HF1. 

The problem was that any file opened by an external application with a native binary file type will throw this error.


UPDATED: October 18, 2018
This was fixed in Portrait Dialogue 6.2 HotFix2
A workaround would be to go into Dialogue Admin, into the Message type options for the message type having this issue, then on the Editors & Viewers tab, and change the Message Viewer to Use default (internal) viewer.