Try these steps:
 
1. Make sure you're set up properly & configured before installing. Check your firewall & modem/router to make sure UPnP is enabled; see  
Connection problems? Check here first! (click on link) 
2. Install  
Java 1.5 (take the JRE) using the "Offline" installer. Don't install online! 
3. Downld the "Offline" LW installer from here 
http://www.limewire.com/english/content/download.shtml
Then install. LW will usually uninstall any previous version/copy at the beginning of installation.