Using the New Outlook for Mac features in business environments
Based on my research, you may consider reauthenticating Salesforce for Outlook by following the steps available in Salesforce for Outlook (SFO) OAuth Reauthentication Steps
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As of the moment, I have not found any official documentation that addresses this issue. Additionally, if this does not help resolve the experience, you may consider reaching out to Salesforce Support for further assistance, especially since you mentioned that this is affecting multiple users.
I hope this provides some additional direction.
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