Unless you deleted it, it should still be in your program files. Go to C:\Program Files\LimeWire\LimeWire.exe, and double click it to run the installer.
If you can't find it, go to Start>Search>All Files And Folders, and search for LimeWire. Then double click on LimeWire.exe.
If you did delete the installer, you can redownload it from your PRO Download Page by entering the e-mail you used to purchase it with here:
http://sales.limewire.com/support/pro_lookup.php. If your PRO Download Page has expired, you'll have to purchase it again or download the Basic(Free) Version.
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