Hi @MichaelS
Please try using CalCheck to check for calendar issues.
The Calendar Checking Tool for Outlook (CalCheck) is a command-line program that checks the Microsoft Outlook calendar for problems. The tool opens an Outlook messaging profile to access the Outlook calendar. It performs various checks on general settings, such as permissions, free /busy publishing, delegate configuration, and automatic booking. Then, each item in the Outlook calendar folder is checked for known problems that can cause unexpected behavior, such as meetings that seem to be missing.
To use CalCheck, the Outlook calendar must reside on a computer that is running Microsoft Exchange Server. The tool doesn't work with IMAP, POP3, or other non-Exchange email accounts.
For how to download and use, please refer to Information about the Calendar Checking Tool for Outlook (CalCheck)
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