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Visit https://powerbi.microsoft.com/en-us/gateway/ and download the Power BI gateway (personal mode) Standard on the server.
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Only chose the standard mode. Personal mode will only allow a data refresh if you are logged into the server, so it will not allow scheduled refresh.
After the download has completed, browse to the files location, right click the application and select Run as administrator - If the installer gives a warning that .NET needs to be updated, go to https://dotnet.microsoft.com/en-us/download/dotnet-framework and download recommended version.
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