Problem: Microsoft does not allow parallel installations for Click-to-Run and MSI in Office and an error message is inevitably displayed when attempting to install Office and Project, Visio, etc. in parallel.

Solution:

1. Install your version of Office and activate it.
2. Now open the registry editor (Windows key + R and enter “Regedit”, confirm with the Enter key)
3. Now go to the entry:

For 32-bit editions (the last folder may vary depending on the version):
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\Office16.PROPLUS

For 64-bit editions (the last folder may vary depending on the version):
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\ProPlus2021Volume – de-de
or
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall \ProPlus2019Volume – de-de
or
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Uninstall\Office16.PROPLUS

4. Create a DWORD with the name:; SystemComponent and the value: 1

This value prevents your Office version from being recognized by the installer (C2R or MSI) and therefore no longer displays an error message.

5. Now install Visio or Project etc. and activate it.
6. After successful installation, you can remove the value again and use your Office package and your parallel installation side by side.