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See Configure Exchange Service Account for Meetical (with Delegation) on how to set permissions for your Exchange Service account.
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Installing the Confluence Outlook Add-in for Data Center / Exchange users
Please note the Outlook Add-in you find in the official Microsoft Appsource store, is only for Confluence Cloud and not compatible with Data Center.
To install the Outlook Add-in for Data Center users, you need to use the XML file which is generated for you in the Meetical Configuration (Go to Confluence Settings and find the option in the left menu).
Navigate to the Admin Section of Meetical in your DC instance. Choose “Microsoft Exchange” as the provider. Follow the Setup, by creating and defining a Service Account with access to the calendars of those users you want to make the Outlook-Add-in available for. Then get the XML file and install the add-in via OWA, Exchange Admin Center, or Power Shell.
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