Can't login to New Outlook (from Windows Mail app) due to tenant error

Question

Hello,

I hope to find you well.

I've been trying to fix this issue desperately, but so far it's has been a very frustrating experience.

To sum it up, I have a personal mail account, and a work mail account.

I've been using the default Windows Mail for ages with both accounts setup, with no problems. However, I've received a notice that Windows Mail will soon stop being supported and that the "New Outlook experience" will be enforced, so I decided to try it out and make the move.

Little did I know it would be a pita to simply sign in to the work account. I've dropped an image below so that you can see what's going on and the error I'm getting.

I have been able to sign in everywhere, except this app. I'm a verified tenant of this organization, as I've set it up myself like all the other accounts.

Things I have already tried:

1. Check Azure AD user settings (found nothing abnormal)
2. Reinvite account as guest, but I can't because it says im already part of the organization as a member.
3. Reset Autodiscover + registry
4. Fiddle with the registry editor to clear Outlook cache.
5. Uninstall Outlook
6. Remove mail profiles from Control Panel > Mail
7. Readd mail profiles using the Microsoft 365 settings
8. Removing the work account from the Outlook app and trying to readd it again.

No matter what I do, I always get this Sign In error. I have tried the official premium Outlook 365 version and the 2019 version on other PCs and I didn't have a single problem signing in.

If this is the new Outlook experience, it's been garbage so far.

I'd like to know if anyone else has experienced this issue so far and if you could help me solving it, because I'm at dead end and the last thing missing is to completely reinstall Windows, which I'm not looking to do for various reasons.

Thank you.

Answer 1

Hi @João Silva ,

Since it's a public forum, I've just removed the email addresses and domain name involved in the screenshots you shared for privacy concern. And considering that the error prompt is related to AAD, so I also added the tag "Azure Active Directory" so that community members there can also take a look at it.

Regarding the error, I understand you have already tried a number of things and have also checked the Azure AD user settings with no luck. Given current situation, I'd suggest click the "Copy into to clipboard" button in the error message, then try reaching out to the administrator of the tenant and share the error details. In this way, they can check the sign-in logs from the Azure portal using the Request Id involved and see if any clues can be found.

Meanwhile, at present you can consider temporarily going back to Windows Mail by following the document below:
Toggling out of the new Outlook for Windows preview

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Answer 2

Hi @João Silva ,

As I don't have a valid Outlook 365 license for myself, I ended up logging off the Office account that had it, uninstalled and went back to Windows Mail app.

Thanks for the share. I've tried searching a lot earlier as well but can hardly find any similar reports or useful information either. So personally, I also think moving back to Windows Mail app might be the better choice at present given the fact that it might be quite hard and time-consuming to solve the error pop-up in your scenario.

Anyways, thanks again for sharing your experience and hopefully this can help others in the community looking for remediation for similar issues. By the way, since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others", I'll repost your solution in case you'd like to "Accept" it as the answer so that it can help increase visibility of this question for other community members.

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[Can't login to New Outlook (from Windows Mail app) due to tenant error]

Issue Symptom:

After switching to New Outlook from Windows Mail app, cannot login in due to tenant error AADSTSD50020, no issue using the same account on a regular Outlook app.

Current status:

"As I don't have a valid Outlook 365 license for myself, I ended up logging off the Office account that had it, uninstalled and went back to Windows Mail app."