Hi @Craig Simpson ,
Welcome to our forum!
What about removing Viva Insights addin and re-add it again?
Since around March 2023 MonthlyEnterprise channel outlook is crashing even in safe mode.
According to your description, i notice that the issue persists in Safe mode. In general, if the issue persists in Safe Mode, the problem may not be related to the add-in. What's the version of your Outlook? (File > Office Account > About Outlook). Please first make sure you have upgraded your Outlook to the latest version.
Considering that it may be caused by the damage of the profile/data file in the Outlook client, it is suggested that you could try to create a new profile(Control Panel>Mail>Show Profiles>add) and add the account for testing to check if there are some differences.
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