external users get this error when trying to access meeting link

Hi @James James

External participants who are invited to a Teams meeting that's scheduled by users in your organization can't join the meeting. Instead, they receive one of the following error messages.

Sign in to join this meeting

This behavior occurs because of the settings that control anonymous join.

If an external participant isn't signed in with a Teams work or school account and tries to join the meeting (as an anonymous user), they receive the message in one of the following situations:

• The organization meeting setting Anonymous users can join a meeting is turned off. If this setting is turned off, anonymous users can't join meetings that are organized by any users in your organization.
• The organization meeting setting Anonymous users can join a meeting is turned on. However, in the meeting policies that are assigned to the meeting organizer, the Anonymous users can join a meeting setting is turned off. This prevents anonymous users from joining meetings that are scheduled by that organizer.

Resolution

To manage Teams meetings with external participants, follow the Plan for meetings with external participants in Microsoft Teams guide and select the correct settings according to your needs.

Here are some example situations.

Allow all types of external participants to join meetings

• Enable anonymous join in the organization meeting settings.
• Enable anonymous join in the meeting policies that are assigned to users in your organization who are allowed to organize meetings with anonymous participants.
• In the external access setting, select Allow all external domains.
• Turn on guest access. To do so, in the Microsoft Teams admin center, select Users > Guest access, and then set Allow guest access in Teams to On.

Block all external participants from joining meetings

• Disable anonymous join in the organization meeting settings.
• Block external access.
• Turn off guest access. To do so, in the Microsoft Teams admin center, select Users > Guest access, and then set Allow guest access in Teams to Off.

Allow only external participants to join meetings as authenticated users that you trust

• Disable anonymous join in the organization meeting settings.
• In the external access setting, make sure that the external participants' domains aren't blocked or are allowed.
• For admins of the external participants' organizations: In the external access setting of the external participants' organizations, make sure that the meeting organizer's domain isn't blocked or is allowed.
• Turn on guest access.

Block only specific users in your organization from organizing meetings with anonymous participants

• Enable anonymous join in the organization meeting settings.
• Turn off the Anonymous users can join a meeting setting in the meeting policies that are assigned to those specific users.

For more information about anonymous meeting join, see Manage anonymous participant access to Teams meetings (IT admins).

If you have any further updates on this issue, please feel free to post back.

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