You can lead a horse to water, but you cannot make it drink.
I've told you what to do. You can either stand there, drink beer and wish it works, or you can get busy and figure out the problem. I don't know what else to tell you. There are only so many things that can cause this...................
From your last description, this could be a bad cable or cable connection, or an intermittent such as a starter "going bad." When was the last time you cleaned and re-tightened the battery posts?