Are you getting the error while trying to install a particular MSI package and not while doing any other. Then I was also in the same boat. I had this error on my home laptop which is running the Windows 10 version.
I have tried enabling the Administrator user by running the following command in the cmd line. (You need to run the cmd.exe “RUN AS administrator” by right selecting the option)
This did enable a separate Administrator account. Mind you, this is separate from the Admin privileges account that you thought you had. Installing from that account did not get the error away, so I had to revert to editing the registry keys. (On editions other than HOME version , you can use gpedit.msc to disable the policy. But since I did not have the gpedit, I went in to edit the registry keys.)
Drill down to HKLM\SOFTWARE\Policies\Microsoft\Windows\Installer
Look for the DWORD(32-bit) Value, DisableMSI (create if not already there) and set it to Hex value 0
This should help you with installing the MSI package.}