That is very odd that the Basic version works but the Pro doesn't. Upgrades for OSX can cause issues with regards to Java. It has been discussed in this or the general osx section of the forum. What you can try to do is remove the limewire receipt & then try installing pro. Double-click the harddrive icon, open the Library, open the Receipts folder, then find the file: Install LimeWire.pkg, delete it and try again. Receipts folder sample image If this doesn't work, then I'd think in regards to Java. Generally reinstalling this http://www.apple.com/downloads/macos...update142.html fixes it. But there's another option also. BTW if it won't let you reinstall Java, then remove the Java 1.4.2UpdateX from receipts & try again.