Finding currently installed MSIs

Originally posted on my old MSDN blog

I was struggling to install some new software (the superb new Live Local 3D view - I had an early internal beta already installed) and then remembered a handy tip.

To find all currently installed MSIs, use the (hidden) folder c:\windows\Installer. It gives you a nice browseable view of the current state of the system, and can be invaluable in tracking down what the system currently thinks is installed.