Tennant connection problem to mail api (Graph)

Question

Hello,

1. I'm trying to send and recieve emails with a c# application.
2. I found out I needed to make some settings in the Azure portal.
   I have ClienId, TennantId and Client Secret.
3. Then I found out I needed to get an Office365 subscription which I did.
4. The error is now:
   {"error":{"code":"OrganizationFromTenantGuidNotFound","message":"The tenant for tenant guid 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' does not exist.","innerError":{"oAuthEventOperationId":"9xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx","oAuthEventcV":"xxxxxxxxxxxxxxxxxxxxxxxxx","errorUrl":"https://aka.ms/autherrors#error-InvalidTenant","requestId":"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx","date":"2024-12-18T08:38:41"}}}
   ( i replaced the id's with x's)
5. The application works fine with another microsoft account but I need to use my personal.
6. It looks like I need to make a setting in Office ADmin portal which I cannot login to with a personal account.

Answer 1

Hi @Frank Van diepenbos

If you are trying to use a personal account to log in to the app and call the Graph Mail API to send an email, then follow this:

First, you'll need to register an app in your tenant that allows personal accounts to log in.

Next, use the authorization code flow to authenticate your personal account and generate an access token. Note that when logging in to a user and requesting a token, you need to change /{tenant_id} to /common.

Finally, call the POST /me/sendMail API to send the email.

By the way, MS 365 license is not required for personal or social accounts. But for work accounts, MS 365 license is necessary.

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Hope this helps.

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