Additional meeting and call-related features and issues within Microsoft Teams for business
Dear Ian,
As a forum moderator, I am not able to check your Microsoft account or the organizer's Teams settings to diagnose and fix this directly. My role here is limited to providing general guidance you can apply from your side. Your Virgin Media alias can receive the invitation, but Teams may not treat it as the same identity as the Microsoft account you sign in with, so it doesn't recognize you.
If this is a normal meeting invitation, try opening the link in a Microsoft Edge InPrivate window, then select Continue on this browser and Join without signing in. Enter your name and, if you're asked, verify your email with the one-time code. This only works if the organizer allows external or anonymous participants.
If the invitation is to join a team or organization, ask the organizer to remove the existing guest invitation and send a new one to the exact email address of your Microsoft account. Guest invitations have to be accepted with the same identity they were sent to, and the organizer's administrator must allow guest access.
If Teams keeps opening the wrong account, sign out first, or select Change on the pre-join screen to pick the correct account.
I hope this helps. Looking forward to your reply.
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