Guests can't login to Teams

[HamishMoffatt]

I have two guests from another organization who I have invited to Teams. They have accepted the invitation, they show as accepted in Entra, and they are listed as being in the group. However when they open their client (web, Mac or iOS), they simply get "we're sorry - we ran into an issue". There are no error codes given.

They were joined to our organization OK until August, when their logins stopped working. We have removed and re-added them multiple times as directed by the support tickets we've opened, but so far nothing has worked.

We've added them in two ways, after first deleting them (permanently) in Entra

- Directly from Teams client

- Invite from Entra, then add to Team once Entra invite accepted

Neither makes any difference. We've waited up to 72 hours for it to take effect.

All our guests settings for Teams are set correctly according to the documentation at https://learn.microsoft.com/en-us/microsoftteams/set-up-guests

Is there something in THEIR organization that they should check? They don't use Teams except with us.

[#2]

Hi @HamishMoffatt,

The guests may be facing issues joining your team due to restrictions set by their organization.

To resolve this, the guests can check with their organization's IT administrator to ensure that:

• Guest access for Microsoft Teams is enabled.
• Access to Microsoft Teams for external users is not blocked

If the issue persists, the guests should contact their organization's IT administrator for further assistance.

There may be specific settings that need to be adjusted in their  tenant.

Key points to remember:

• Guests need a valid email address not associated with an existing Microsoft account.
• Guests must be invited to a team by a team owner or administrator.
• Guests must accept the invitation to join the team.
• Guests must be granted access to team resources by a team owner or administrator.

Collaborate with guests in a team (IT Admins) | Microsoft Learn

Collaborate with external participants in a shared channel (IT Admins) | Microsoft Learn

Guest access in Microsoft Teams - Microsoft Teams | Microsoft Learn

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Kindest regards,

Leon Pavesic
(LinkedIn)

[#3]

Thanks@LeonPavesic . All the documentation is written as instructions for the host organization, not the organization containing the guests, so I am not sure which settings to check exactly in the guests' organization.

In our organization we have users with a mix of E1, E3, F3 and Business Standard licences. I am told no further licences are necessary for our guests.

We have Security Defaults enabled on our tenant but no other conditional access.

[#4]

Hello,

we have the similar situation in our Orga. It seems like people that have been working with us for weeks and months are getting kicked out and cannot re-login. They need to clear the browser cache and receive a new invitation to join the team for another few weeks, but the app still doesn't work.

Is it somehow related to the policy, that guests without a valid license are getting kicked out after 30 days?

Best,

Max