This seems to have recently become a problem for quite a few people. See the first fix in the link below. I also gave you a few other options to try if that doesn't help. I am also assuming you have Vista. This seems to be where the problem is.
You might take a look at the link below. Seems to be helping a lot of other people.
1.
Vista Limewire Fix Once And For All!!!
Try these fixes if above is no help.
2. Try uninstalling all versions of Java from the add/remove programs and then re-install the JRE 5.11 offline version....
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11
3. If that does not help with your problem try deleting your preference folder/s...
Fixes for Limewire when LW isn't operating as it should LimeWire Pref Folder in Vista
4. Supply these details If all else fails.
System details - help us to help you -> Provide these details when you post!!!.
