Microsoft
MicrosoftUnfortunately it just says "User mailbox is marked as undiscoverable by Teams middle-tier service." and i had that already from Teams Logs "isMailboxDiscoverable: false"
So some info from the backend where it failed would be great to investigate further e.g. host xy.acme.com/Autodiscover returned 5xx or invalid cert etc.
I'm already through all the articles like https://docs.microsoft.com/en-gb/microsoftteams/troubleshoot/known-issues/teams-exchange-interaction-issue +removed preauth completely from ReverseProxy, checked IIS logs (autodiscover.json success from Useragent SkypeSpaces), disabled/enabled OAuth on VDir, ...
Weird is: Test-HMAEAS.ps1 returns "mail.acme.com and invalid certificate" at the end which is weird as that name is unrelated to Exchange and the old decomissioned MX mailflow/http redirect to website <- is there some guessing machanism that has this as a fixed name? (trying to have the customer delete the DNS records)
Two other things i feel are special about this customer to my others:
1) we switched from modern Hybrid to Classic (for Teams calendar access of OnPrem Mbx)
2) they started with free Teams licenses and are now switching to "O365 business.."
We opened a service request but any more tips would be welcome
But most of all if you increase the debug info, the tool will be the perfect troubleshootingtool to see "what the server is seeing"
Thanks Thorsten
PS: the Autodiscover and EWS tests themselves were successfull so it might "just" be a incorrect Flag that prevents him from trying?
The Office 365 Autodiscover V2 endpoint returned a valid response. -> Request: https://outlook.office365.com/autodiscover/autodiscover.json?Email=jdoe%40acme.com&Protocol=EWS Response: {"Protocol":"EWS","Url":"https://as.acme.com/EWS/Exchange.asmx"}
Exchange Web Services (EWS) service request was successfull. -> Additional Details: GET request URL: https://as.acme.com/EWS/Exchange.asmx Server name: FRAMAIL1
