Microsoft did not have the "full faith and credit" of the Gates family. His family figured it would burn out and he'd return to college, per what Bill has said on the matter. They were less than thrilled with him dropping out. He received $0 funding or help from them in regards to Microsoft getting started.
It was a million dollar business, completely independent of the Gates family or its connections, while it was operating in New Mexico. Bill and Paul had sales almost from day one.
Exactly. Also having that family meant he could take risks that others couldn't simply because he knew the family would bail him out (personally, not the company) if things didn't work out.
About his family, at least according to Phil Greenspun
It was a million dollar business, completely independent of the Gates family or its connections, while it was operating in New Mexico. Bill and Paul had sales almost from day one.