Vuze suddenly stopped working on my mac. How can I get it back?

I’ve used Vuze (formerly Azureus) for years now with no problem. The other day, out of nowhere, it stopped opening. I tried uninstalling and reinstalling it, updating java, turning off the computer (an ibook from 2005 running OSX 10.4.11), and nothing’s worked. When I try to reinstall Vuze, I get the message “an error occurred. java.io.IOException: no such file or directory Error log:”
Can anyone help?