MicrosoftAjax.js fails to load for Outlook Web App (OWA) Addin RRS feed

  • Question

  • I'm working on an Addin for OfficeMail that should be loading on OWA, sometimes it loads perfectly fine while sometimes it errors with MicrosoftAjax.js failing to load.
    The Addin also activates in Outlook for Windows Desktop and works for me everytime, but on the web app there's seems to be inconsistency.

    I'm using Office.js from ""

    I'm attaching the chrome dev tools network output, I've tested it on FireFox and Edge also with same inconsistent results.
    Help will be most welcome.

    Tuesday, May 16, 2017 3:31 PM

All replies

  • Hello,

    It shows you get 403 forbidden and 401 unauthorized error at the beginning for your request, I think you need to check these error firstly.
    I would suggest you use fiddler to caught request in Outlook desktop.



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    Wednesday, May 17, 2017 8:22 AM