If you’re running as a non-admin (which you know you should be), you are used to Right click… Run as… if you need to execute an application that needs admin privileges. This is easy and good. This even works for installers that are packaged as EXE. The pain is when you want to install a MSI package. Right click… and there is no Run as… option. So you do what I do, which is launch a command prompt as an admin user, browse to the directory containing the MSI package, and then execute from the command line. Or if you’re Michael Willers, you hack the registry and add an Install as… option. Doh! Why hadn’t I thought of that? Great idea, Michael. His steps are reproduced below:

1. Run regedit.exe under an account with administrative privileges
   
2. Create the key HKEY_CLASSES_ROOT\Msi.Package\shell\runas\
   
3. Set the default value to Install &as…
   
4. Create the key HKEY_CLASSES_ROOT\Msi.Package\shell\runas\command\
   
5. Set the default value to msiexec /i “%1”