How to play offline without connecting to Steam (Score 1)

In a Steam FAQ I read that you should be able to play offline without connecting up to Steam - you just need to disable your internet connection before you start up the Steam program. Alas, when I try this I get the message 'Offline mode is unavailable because there is no Steam login information stored on this computer. You will not be able to use Steam until you can connect to the Steam network again.' Why Steam occasionally loses my local login information I have no idea. Makes me want to LET OFF STEAM!!