Hi @labviewman,
you have to be connected over the internet to be able to download the spacedesk Windows Viewer app from Microsoft Store or the Windows 7 desktop version from the website https://forum.spacedesk.net#download.
Once you download and install spacedesk Viewer and Server/Driver, internet connection will not be needed anymore.
Just make sure that your primary and secondary machine are connected on the same local area network.
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