OAuth authentication configuration fails - Exchange | Microsoft …
Jun 25, 2025 · When you run the Hybrid Configuration wizard, OAuth authentication configuration fails, and you receive the following error message: Exchange OAuth authentication couldn't …
Microsoft Outlook Exchange Service OAuth Token - Invalid Client
Jun 10, 2025 · It sounds like from the error that you didn't register the application as a public client the easiest way to confirm that is check the application registration manifest you should see …
OAuth Certificate Missing in Exchange - Fix Guide 2025
This guide shows you how to verify, create, and configure OAuth certificates to restore full authentication functionality. Our Exchange Authentication Support team regularly resolves …
How to Troubleshoot Office365 IMAP AUTHENTICATE XOAUTH2 …
Apr 8, 2024 · Check to see if your Client Secret is entirely expired, meaning it’s not even possible to refresh anymore. In this case, you’ll need to create a new client secret in MS Entra ID for …
InvalidOAuthTokenException - Microsoft Q&A
Nov 27, 2025 · The error message you are encountering, InvalidOAuthTokenException, along with the HTTP status code 401, indicates that there is an issue with the OAuth token being …
FIX: Outlook Authentication with Office 365 Fails. (Solved)
May 12, 2025 · According to Microsoft the authentication issue can appear on Windows 10 v1703 and later, because of missing package information about either the Active Directory …
Exchange Online - Troubleshooting Expired or Revoked OAuth Token
Jan 10, 2025 · Summary: There are several situations where the OAuth Token for Exchange Online needs to be refreshed. This article details some of the reasons and how to refresh the …
How to Fix Microsoft 365 Authentication and Initialization Errors …
May 4, 2025 · Authentication or initialization errors within Microsoft 365 applications, notably seen with Outlook on Windows 11 and Windows 10, represent a frequent and often disruptive …
Need Help: IMAP OAuth2 Authentication Issue for Outlook.com
Nov 21, 2024 · Hey everyone, we're hitting a wall trying to get IMAP access for an Outlook.com mailbox using OAuth2. We're always getting an AUTHENTICATE failed error, even though …
Office 365 XOAUTH2 for IMAP and SMTP Authentication fails
May 4, 2020 · Recently the support for OAuth 2.0 for IMAP and SMTP in the Exchange Online has been announced. Following the guide I've set up the application permissions and IMAP …