Accessing Microsoft Teams using organizational or personal credentials
To eliminate Office applications as a factor, we recommend that federated users in an iOS environment test certificate-based authentication in the Safari browser by following the steps outlined in the "more information" section. The typical experience for iOS users who cannot authenticate on https://portal.office.com on a Safari browser is as follows:
The user is not prompted as expected to approve the use of their user certificate after clicking the entry using an X certificate link. 509.
The federated user is on a non-responsive STS home page or moves to the standard STS home page, where they are requested as follows:
Select a certificate that you want to use for authentication. If you cancel the operation, close the browser and try again.
Note If other authentication methods are enabled in AD FS, the user will also see a link that says "enter other options". If they click here, they will return to the STS home page.
Both experiments fail with the following error:
Safari was unable to open the page because the server stopped responding.
Reason:
The certificate chain is incomplete because the issuing subordinate certification authority certificate is not retrieved by the device as expected when the MDM policy sends only the root certificate to the Apple device along with the SCEP profile.
The iOS device does not properly acquire the file *. Issuing CA's CRT, even if the AIA path in the user's certificate has a valid URL that points to the file *. Issuing subordinate certification authority CRT.