Updating a calendar invite and erroneously the update removes resource and/or invitees

Question

I have delegate access to my manager's calendar. For a few meetings with external parties and sometimes a resource (internal room), when I make an update to the calendar invite, people and/or the room are being removed. They receive a cancellation for the meeting they are required. This has happened in 4 instances. First time I removed one person, and the invite removed 3 (all internal). Second time I added one person and the invite removed me and another person (external). Third time I added a room and the invite removed an internal person. Fourth I added an external person, it removed me, then removed another internal person when I tried to re-add myself. Room was removed the last time around. I have full editor access. What is going on?

Answer 1

Hi Shannon Kelliher,

Welcome to our forum!

Does the issue occur recently in Outlook Desktop Client?

How did you update the meetings? Could you please describe the detailed operations?

What is the version of your Outlook? It is recommended that you please check the Outlook client version (File>Office Account>Product Information) and try to upgrade to the latest version to see if the problem is resolved. 

To further confirm if the issue is more related with Outlook Desktop Client, it is suggested please log your account in to web version and do the same test to see if the issue persists.

Meanwhile, here are some steps you may want to take:

1. Ensure Correct Delegation Settings

• Verify you have "Editor (can read, create, and modify items)" access, not just "Author." Go to File >Account Settings > Delegate Access to confirm.

1. Check Room/Resource Permissions

• Ensure the room allows edits by delegates (some require organizer-only modifications).

1. Repair Outlook Data Files

• Run SCANPST.EXE on your OST/PST files (corruption can cause sync issues).

In addition, here are workarounds you may refer to:

1. Edit Directly in the Manager’s Calendar (Not from Forwarded Invites)

• As i know, this often happens if the meeting was originally booked in a different calendar (e.g., your manager forwarded it to you rather than you editing it directly in their calendar).
• Open your manager’s calendar directly (not from a forwarded invite) and edit there. Avoid opening the meeting from your own inbox.

1. Use "Update" Instead of "Send Update"

• When you edit a meeting, Outlook sometimes treats it as a "new" meeting series, causing it to cancel the original and send updates that drop attendees/resources.
• When modifying, try saving changes first (Ctrl+S) before sending updates. Sometimes Outlook behaves better when you save >then send updates separately.

1. Re-add Dropped Attendees Manually

• If someone gets dropped, manually re-add them before sending updates.

1. Switch to Online Mode (If Using Cached Exchange Mode)

• If your manager’s calendar is in Online Mode (Cached Exchange Mode disabled), and yours is in Cached Mode (or vice versa), updates may not sync correctly.
• Go to File >Account Settings >Account Settings >Double-click Exchange account >Uncheck "Use Cached Exchange Mode" (temporarily) and test.

Hope it helps.

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