Able to successfully connect to outlook/exchange online with EWS using Microsoft Identity Platform.
But getting following exception:
"Too many concurrent connections opened., Cannot open mailbox (ErrorInternalServerError)"
This has started happening when using OAuth, which was not the case with basic authentication.
Also came across following issue, which discusses the same thing. Unable to figure out how to apply the solution on Rebex EWS library?
Can you please help?
Update: This has been resolved in Rebex Secure Mail 2020 R4.
I tried to reproduce the issue described in the link you provided, but the issue did not manifest. We did a search what mentioned header "X-AnchorMailbox" from the same link is used for and it turned out it is used when you need to impersonate a user in certain circumstances. See this Microsoft document.
Are you using impersonation? Can you share more information about the issue? How can we reproduce it using our EWS component? Which server you are connecting to?
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