External users in Teams meeting

There is a few things that may resolve this, try one of the below:

1. Incorrect Email Address Format

• Verify that the email address is correctly entered and follows the standard format (e.g., user@example.com). A small typo can prevent Teams from recognizing the address.

2. Guest Access Configuration

• Ensure that your organization allows Guest Access in Teams. Guest Access must be enabled at the organizational level by an administrator for users outside your organization to join Teams meetings or channels.
• Go to Microsoft Teams Admin Center > Org-wide settings > Guest access and check that guest access is enabled.

3. Azure Active Directory (AAD) Settings

• Microsoft Teams relies on Azure AD to manage external users. If the user hasn't previously been added as a guest in Azure AD, Teams might not recognize them.
• Check with your IT administrator to see if the external user has been added to your organization's Azure AD.

4. Conditional Access Policies or Security Groups

• If your organization uses Conditional Access Policies or restricts access via security groups, certain email domains or users might be blocked from joining. Confirm with your admin if there are any restrictions in place that might affect guest users.

5. Using an Up-to-Date Version of Teams

• Sometimes, outdated Teams clients have issues with external invites. Ensure that you and any external users are using the latest version of Microsoft Teams.

6. Scheduling the Meeting Through Outlook

• If you’re unable to add the external user directly in Teams, try scheduling the meeting through Outlook and adding the external participant's email. This often bypasses some of the restrictions that Teams might impose.