Hi @Adrianna Wells,
Thank you for posting your question in the Microsoft Q&A forum.
I understand that you are experiencing difficulties with the Outlook rule for filtering meeting invites as a delegate.
Could you please let me know which version of Outlook you are using? Based on the link you attached, you may use Outlook MAC. Honestly, there are limited resources in my environment that I cannot test on Outlook MAC.
Additionally, have you tried creating this rule using Outlook Web?
So, I suggest some places you should check to resolve this issue:
1. Ensure the sixth delegate has the same permissions as the others.
Go to File > Account Settings > Delegate Access and verify their settings.
2. If other rules are interfering, try moving this rule to the top of the list.
Choose Gear settings > Mail> Rules> select the rule> Move Up option. (direction symbol up)
3.Double-check the rule conditions to ensure they match the existing ones.
If using specific keywords, verify they are formatted correctly.
4.Delete the rule you created for the 6th person and recreate this rule for them on Outlook web to see if it works or not.
5.Some versions of Outlook have a limit on the number of recipients a rule can apply to. To know more, please refer to this link Exchange Online limits - Service Descriptions | Microsoft Learn>I can see that the Forwardee limit is 10, so I'm not so sure this is your issue. However, you may try creating a separate rule for the 6th person.
6.Some Exchange configurations limit rule execution based on mailbox size or complexity. You may check with your IT admin if there are any restrictions.
If none of these steps resolve the issue, it might be helpful to provide more details about the rule and any error messages you are receiving or the screenshots of your issue. This can assist in diagnosing the problem more accurately.
In the meantime, we suggest you should go to Microsoft 365 Admin Center >Help & support (at the right bottom) to raise a ticket and attach the EML file* for them. Because they have more tools and resources to check and diagnose your issue. We both two teams will make efforts to give you as much as directions we can to resolve your issue. *Please generate a report in Outlook settings to check the details >they'll send you an email> please save it as EML file.
Thank you for your understanding and patience.
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