This error normally occurs when an error occurs in one of the C/AL functions called by the ForNAV DLL.
It can also occur when the users are asked if they want to allow the client add-in to run. If the user answers “no” then this message is shown. In order to resolve this problem the user has to restart the NAV client and choose yes when this question is shown.
Since version 22.214.171.1247 the exception message is shown in a message box if you are running the code from a normal client. You can use this message to determine where the problem is. In case you need support, you should make a screenshot of this message and send it with your support question to your NAV partner.