Hi @john in t veld ,
Glad to know that your issue is resolved now! Since our forum has the policy that The question author cannot accept their own answer, I would make a brief summary of this post so that other forum members could easily find useful information here:
Issue Symptom:
oAuth ews o365 - error 403 forbidden
the application ID being incorrect in AAD
Solution:
Change to the correct application ID
You could "Accept Answer" for this summary to close this thread, and your action would be helpful to other users who encounter the same issue and read this thread. Thanks for your understanding!
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