Sounds like you might be downloading .wma files. If that's the case, have a read through this
What you should know about WMA Files

Ummm can I just ask where you bought LW & how much you paid? LW basic is free & Pro costs $18.88 for 6 months of free updates & email support. The only official (safe) site for downloading either version is www.limewire.com

Buying Pro doesn't make it legal for you to download copyrighted files. Laws about this differ from country to country & you'd have to check your local laws to find out where you stand with downloading files. Some scammers do try to sell you LW based on the lie that once you pay for the app, everything magically becomes legal

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