email address isn't permitted by host

What is the link for? To join your meeting, or to join your Teams channel?

This has to do with the meeting policy settings, sometimes that's not enough, it can be due to whole organization's policy settings. If the person you invited is using a personal Microsoft account, setting it to "everyone" is typically not enough. It also needs to allow users that are not managed by any organization in Admin Center.

While you work with your organization admin to get this changed, users you invited can also join this way without being restricted.

Have them paste the link to a web browser. When prompted to use the app, don't use it. Stick with the web option. When prompted to sign in, don't sign in either. This way they will be let in. They will have a chance to put in their desired display name.

Hi @Aune, Sara [FH], 

I hope you're doing well today. 

Based on the information you shared that a participant is receiving an error stating their email address is not permitted by the host when attempting to join a Microsoft Teams session. This behavior usually occurs when the meeting's access configuration or organization-wide policies restrict external or anonymous users from joining. This often happens if the lobby settings are too restrictive, if the guest's domain is not explicitly allowed, or if there is an identity conflict caused by cached credentials in the attendee's browser. 

To address this issue, please try the steps below in order: 

1/ Verify that the meeting options are configured to permit external participants 

• Navigate to your Teams calendar, open the specific meeting invite, and select Meeting options. 
• Change the Who can bypass the lobby? setting to Everyone to ensure external guests are not automatically rejected. 
• 
• Save the configuration and have the user attempt to join again to see if the access restriction is lifted. 

2/ Ask the guest to join using an InPrivate browser window to clear identity conflicts 

• Have the participant open a new Incognito or InPrivate window and paste the meeting link directly into the address bar. 
• Ensure they sign in with the exact email address that received the invitation to avoid authentication errors. 
• This process prevents the browser from attempting to use a different, uninvited Microsoft account that may be signed in elsewhere. 

3/ Review tenant level external access settings and contact support if necessary 

• Ask your IT administrator to visit the Teams Admin Center and verify that Guest access is on in Guest access. 
• 
• Confirm that the Allow all external domains is chosen in the external access. 
• 
• If the issue remains unresolved, please have your IT administrator open a support ticket in the Microsoft 365 Admin Center(admin.microsoft.com) for a deeper investigation into the backend logs. 
• For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin. 

I hope the information I shared earlier was somewhat helpful in addressing your issue. If you have any further questions or updates, please don’t hesitate to share. 

Thank you for your patience and your understanding. I look forward to continuing the conversation.

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.