CryptoLocker is a ransomware program which encrypts almost all of your files. It affects a number of file extensions, and then locks your desktop, saying that if you want to restore your files and get your computer back, you need to transfer a predetermined release fee via alternative payment systems. These systems are used in order to target a wider audience. However, you should never pay a single cent to CryptoLocker. Refer to the link above for more detailed information on this infection, and remove CryptoLocker immediately.
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