Changing Steam install drive

It is possible to install Steam apps and games on external HDDs and pen or flash drives. Steam settings prompts you to select a folder to put your library in, which means that all necessary main game files are contained within one folder. By choosing a folder on an external drive you make the installed game 'portable'.

There are a few exceptions to this where some games require and install extras files on your physical PC when you first start them up, for example, a DirectX version or an SDK. This will pose no problems unless you require to reformat or reinstall your operating system in the future.

Ensure that (1) Steam never automatically starts up when you switch on your PC and (2) you have your external hard drive already plugged in via USB before connecting to Steam. Steam will then detect that your game files are installed ready to load up and and play.