You really should say what your operating system is! You posted in the "Other Operating Systems" forum, so we don't know what you are using. Your problem will happen sometimes in Linux, so I'll give you instructions for that. If you aren't using linux, then please reply back with more information.
Linux instructions:
Well, limewire, I believe, uses java, so you will need to do some configuration to allow your computer to run java programs. Even if you can run java applets on the web, you might not have your java programs able to run.
Here are some instructions on how to set up java. You might have already done the first part; it is how to get java running in your browser. The second part will describe how to get java programs working on your desktop. You didn't say what distrosThese are instructions for Fedora Core, but they *should* work for other distros as well.