Run MSI files as administrator from a user account

.msi files can be executed with msiexec.exe, so in combination with the runas command, you could accomplish what your want:

runas /user:administrator "msiexec /i <path and filename of your msi>"

As a full-path to the file is recommended, it might need quotes around it and you need to escape them then with a backslash \:

runas /user:administrator "msiexec /i \"<path and filename of your msi>\""
                                      ^^                               ^^

You can always open a command prompt as an administrator (either right-click runas or start->run->runas /user:administrator cmd), change to the directory where your MSI exists, and execute msiexec /i product.msi

Or add this to your register: HKEY_CLASSES_ROOT\Msi.Package\shell\runas\command Values: Install &as... HKEY_CLASSES_ROOT\Msi.Package\shell\runas\command Value: msiexec /i "%1"