Airlines Perogative

I have recently come up against this. An airline can refuse you at the last minute if they are nervous about anything, even though you have paid for your ticket, visa, etc.

Do you have any experiences where an airline refused to carry you? If so, what were the circumstances, and how did you solve the problem?

First you name the airline + the problem, so others are aware of it.

Second you never use the offending airline again.

Example, Qantas who refused to honour their SYD-HNL segment of my RTW in a timely fashion & Air Canada just for having pretentious rude staff & unwarranted delays. Both on my no fly list.