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We can discuss issues about installing the Project client on the Q&A forum.
Are you installing the retail version(C2R,16.0) or the volume license(MSI,16.0) version of Project Professional 2016? (C2R and MSI are installation technologies, and 16.0 is the version number. )
- If it is a volume license version, you may not be able to install it together with O365(C2R,16.0).
The official KB states:
"You can't install two products together that have the same version but use different installation technologies."
For more information, please refer to: Supported scenarios for installing different versions of Office, Project, and Visio on the same computer.
- If it is a retail license version, is there any error message when trying to install Project Professional 2016? If so, pelase describe it in detail or share a screenshot with us.
Besides, have you installed other versions of Office/Project/Visio before? Please make sure you have completely uninstalled them.
Hope the inforamtion could help you. Any updates, please let me know.
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