Here's a good start to explaining the animosity. Microsoft spent billions to make sure companies didn't adopt open source software. It wasn't just the SCO money. There was also an associated PR and marketing FUD (Fear-Uncertainty-Doubt) campaign claiming that open source software would destroy your company through lawsuits.
Microsoft CEO Steve Ballmer referred to Linux in 2001 as "a cancer that attaches itself in an intellectual property sense to everything it touches".
Microsoft CEO Steve Ballmer referred to Linux in 2001 as "a cancer that attaches itself in an intellectual property sense to everything it touches".
http://en.wikipedia.org/wiki/SCO%E2%80%93Linux_controversies...
http://en.wikipedia.org/wiki/GNU_General_Public_License#Micr...