Hi @George Pryor ,
Thanks for your update here.
May I know what's the version of your Outlook? (File > Office Account > About Outlook). Please make sure you have upgraded your Outlook to the latest version.
Here is some information about my tests:
- Using Outlook desktop client Version 2008(Build 13127.21348) to manually forward external meeting invitations(HTML format) to internal recipients, with "When sending meeting requests outside of your organization, use the iCalendar format" Option unchecked, the internal recipient receive emails like below, seems normal and can successfully join in the meeting via the join link.
- Using Web mail to do the same thing, the internal recipient receive emails like below, different from the link above but can still successfully join in the meeting via the link.
So, how does your issue look like? Similar as the situation 2? Please make sure you have updated both your Teams and Outlook to the latest version and see if the issue has any difference.
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