There are web sites that write how to modify Windows to run from USB but it's not supported.
I want to boot my laptop from an external source other than my onboard hard drive. I disabled my onboard drive and selected to system to boot from my external source. Everything goes well until after the Windows startup screen. When it gets to loading a certain driver the system crashes and reboots. I've tried it in all modes ex. SAFE MODE. Please help! I know that this can be done.