Click-to-Run is the technology used to install Microsoft 365 subscription and most versions of Office 2013 and newer. Windows Installer technology (MSI) was used to install the volume license editions of older versions of Office 2016 and older, such as Microsoft Office Professional Plus and Microsoft Office Standard.
You can't install the same version of Office products that use two different installation technologies installed on the same computer. This also applies to standalone applications like Access, Visio, Project, Skype for Business, or OneDrive for Business.
You'll get the following error message if Office detects this incompatibility:
Note: In some cases, you also can't have two different versions of Click-to-Run applications on the same computer. For more information, see "Stop, you should wait to install Office 2016" error.
What can I do about this error?
Uninstall the Windows Installer (MSI) version of Office
You can stay with the Windows Installer version of Office and not install the Microsoft 365 Click-to-Run version you were trying to install. Or, do the following:
Follow the steps in Uninstall Office from a Windows computer to remove the Windows Installer version of Office.
Retry the installation of Office you were doing when you got the error message.
For volume license versions of Project or Visio, use the Office Deployment Tool (ODT) to install a Click-to-Run version
If you have a volume license for Project 2016 or Visio 2016 and you’re trying to install the Click-to-Run version of Microsoft 365 Apps for enterprise, you can use the Office Deployment Tool to download and install the Click-to-Run perpetual (stand-alone) versions of Project 2016 or Visio 2016. See Use the Office Deployment Tool to install volume licensed editions of Visio and Project.