Installation Problem...

[SpArKs]

When I click to install HL2, Windows installer says "preparing to install" for a long time, and then comes up with a message saying

"The windows Installer service could not be accessed. This can occur if you are running windows in safe mode, or if the windows installer is not correctly installed. Contact your support personnel for assistance.

Microsoft have been no help as of yet. I am not running in safe mode and have never has this problem before.

 

[Beerdude26]

This sometimes happens when you are trying to install the game on an account with limited administrative powers. You'll need an account with full administrative powers to install the game.