know-it-all - someone who thinks he/she knows everything and refuses to accept advice or information from others

This kind of person usually has an negative attitude and not only refuses advice or information from others, but similarly drives away (by attitude) those who would be willing to help.

My experiences with these personalities show they are usually good at very few things, but know rather little about most others.  They just plow through life doing a less-than-adequate job at most everything - thinking they are as good or better than anyone else at it. They are also very lazy (probably why they never took the time to learn a another way of doing a particular chore).

See also: this

(Coming soon examples)