Java code for reading emails using IMAP with Oauth2 errors with "A1 NO AUTHENTICATE failed"

Question

We need to read emails for a batch process using OAUTH2 with IMAP in our Java Code. We followed the instructions from here: https://learn.microsoft.com/en-us/exchange/client-developer/legacy-protocols/how-to-authenticate-an-imap-pop-smtp-application-by-using-oauth.

We are now getting this error : A1 NO AUTHENTICATE failed.

The java code I followed is from here : https://ralph.blog.imixs.com/2022/10/24/how-to-access-outlook-office365-com-imap-form-java-with-oauth2/

Below are the following things I did:

• Registered the application
• Gave the permission "IMAP.AccessAsApp" in API Permissions under "Office 365 Exchange Online (1)"
• Granted admin consent in API Permissions page.
• Generated the client secret
• Used the client secret and Obtained the access token as per the java code in the above link.
• Registered service principals in Exchange by running the following commands in my windows powershell:

Install-Module -Name ExchangeOnlineManagement

Import-module ExchangeOnlineManagement

Install-Module -Name ExchangeOnlineManagement <organization id>

    New-ServicePrincipal -AppId <Application id> -ServiceId <serviceid> -Organization <org id>

• Added mailbox permission using the following command in powershell:

Add-MailboxPermission -Identity "useremaild" -User <serviceid> -AccessRights FullAccess

This is what I'm trying to achieve: https://techcommunity.microsoft.com/t5/exchange-team-blog/announcing-oauth-2-0-client-credentials-flow-support-for-pop-and/ba-p/3562963

Answer 1

Hello Vishnu,

Can you try adding the following permissions to the registered app?

(cited from https://learn.microsoft.com/en-us/answers/questions/1230605/a1-no-authenticate-failed-using-javamail-and-oauth)

Perhaps you are missing some permissions and this is causing issue when trying to authenticate.

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If this is helpful please accept answer.

Answer 2

is the issue resolved

We are getting the same error