I recently ran into an issue trying to fix a failed deployment of Flash Player. To get around this, I tried to just run the msi manually. When I did this, even though I was logged in with an account with admin rights, I got an error message saying that I did not have admin rights, and would need to have them to proceed. This alone was odd, but I figured okay, I’ll just right-click and select Run as administrator. Unfortunately though, this was not an option. There is, however, a proper way to do this.
Next, navigate to the location of the msi that you wish to install. The msi that I am installing in my example is flash-15-0.0.239.msi. Once you are there, use the Windows Installer (msiexec) command to install the msi.
For this example, the command would be: msiexec /i flash-184.108.40.206.msi
From there, the installer should run with no problems.