When trying to deploy the Office 365 add-in, one of our customers encountered the following problem:
Add-ins are loaded inside Word Desktop and Word Online. When one of the buttons is pressed, an error message appears: "Sorry, we could not download the application because your browser version is not supported. Click here to view a list of supported browser versions."
Relevant Versions: IE 11 42 Word O365 ProPlus 1705 Update (Current Channel)
The version of Internet Explorer has been completely updated, and we have seen how it works for this version of IE. It is possible that there are some security settings that prevent Word from loading the add-in, however I cannot find any information about this.
Does anyone know if there are settings that can lead to this behavior?
Thanks in advance!
Edit 1 This is an error message that appears when one of the buttons tries to open TaskPane. Other buttons that execute some JavaScript will display an error dialog with more or less the same text. I am sorry that this error message is Dutch, but I have not yet found a way to reproduce it in the English system.

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