If you are running the On-Premises version of Microsoft Dynamics 365 Business Central, you can install the ConnectIT 365 app using Windows PowerShell and the app runtime package provided by your implementation partner.
To install or upgrade the ConnectIT 365 extension, start the Business Central Administration Shell.
This will open PowerShell with the NavAdminTool module loaded.
This will allow you to use the cmdlets for installing and upgrading extensions.
If you are installing ConnectIT 365 for the first time, please follow this guide from Microsoft.
If ConnectIT 365 is already installed, and you want to upgrade the app to a newer version, please follow this guide from Microsoft.
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