What's the exact error that you're getting? Where did you download LW from? Did you buy & try to download Pro from the official site Lime Wire » Official Website & Free Download, BitTorrent « or did you try to download it from somewhere else? Have you run a virus scan?

Try downloading AVG Free AV. Download it, update it & scan your computer.
AVG free

If you need more help, try one of the sites below...they offer specialised help with malware removal.

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