Hi @Moore, Wanda (NBCC) ,
Welcome to our forum!
According to your description, i notice that the Send update options disappear before you send the meeting update. As i know, it is related to a recent MS Office version update:
More information: "Send updates" prompt not displayed when updating meetings.
It's suggested that you could try to disable Turn on shared calendar improvement via File -> Account Settings -> Account Settings -> select your account and click “Change” -> in Exchange Account Settings window, click “More Settings”.
Hope to help you!
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