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Installing Visio/Project volume license on top of Office365PP existin…
…g install
The caveat is very confusing, you can install Visio perpetual on top of O365PP but you have to use different channel when you do setup.exe /download and change the channel to Monthly/Broad depending on O365PP install when you do setup.exe /configure
Volume licensed (aka "perpetual") versions of Project 2019 and Visio 2019 support all the same channels that Microsoft 365 Apps (previously named Office 365 ProPlus) do.
So if you are doing /download, you should set the Channel attribute in the Add element to the same channel as the Microsoft 365 Apps install on the device.
If you are installing directly from the internet (/configure), don't include the Channel attribute. Install is smart enough to see what channel Microsoft 365 Apps is using and have Visio or Project install use that channel.
Although channels aren't that significant for perpetual products, because they don't get any new feature updates after they ship (which is what channels are used for in Microsoft 365 Apps).
