I have a friend with a Mac which runs OS/X 10.5 (Leopard).
He has minimal computer experience.
He says that EVERY application excluding Minecraft fails to open with an error message resembling "The application quit unexpectedly".
Does anybody else have an idea how to solve this?
I extracted a bit more information out of him. He says he had a different (newer) OS, but he deleted a file which caused his computer to crash. He installed Leopard, which fixed his computer. I can't figure out whether the problem started directly after he installed Leopard, or some time after that. He always answers a different question from what I am asking.