"You have a Windows Rights issue, and Windows 10 manages user rights differently. Make sure to Install QB "for all users" and "run as Admin."

Another one of those hidden gotchas that I would have known had I spent a month reading QB support forums before attempting to use the product? I will give it a try, thankyou.

A VC once told me: the most investable software companies are those most loathed by their customers. It means the product is so sticky that once you start using it, you can't leave even if it is horribly buggy and even if the company exploits its customers terribly. The archetypal example he used was Oracle, but I think Intuit give them a run for their money.