The word problem is connected with the word "solution." There is usually some specific way to resolve a problem. If there's a problem with your computer, the computer repairman can fix it. If you have a problem in your relationship, you can talk to the other person to find a solution.
The word trouble is more connected with general difficulties. We often use the phrase "having trouble" to mean "having difficulty":
I'm having trouble sleeping. = I'm having difficulty sleeping.
If someone "is in trouble" or "gets in trouble," it means they are in a bad situation:
The boy got in trouble for stealing a toy from the store. or ( he will be disciplined)
If sales don't start improving soon, our company will be in trouble. or ( the company will have difficulty surviving)
The word problem is countable, and the word trouble is usually uncountable. We can say "a problem," but not "a trouble."
There's a problem with my online bank account.
I'm having some trouble logging into my bank account.
The speaker talked about five major problems in society. (notfive troubles)
Master two key components to effectively use the overhead projector in a presentation environment. The first is to understand how your particular projector works and the second is to gracefully integrate your use of the transparency film with the projector. When this is done well, the overhead projector blends into the background and your audience focuses on the projected images rather than the hardware.