"All your personal files on this computer are locked and encrypted by Locker v1.20. The encrypting has been done by professional software and your files such as: photos, videos, and cryptocurrency wallets are not damaged but just not readable for now. You can find the complete list with all your encrypted files in the files tab.
The encrypted files can only be unlocked by a unique 2048-bit RSA private key that is safely stored on our server till 28/05/2015 00:04:22. If the key is not obtained before that moment it will be destroyed and you will not be able to open your files ever again.
Obtaining your private unique key is easy and can be done clicking on the payment tab and pay a small amount of 0.1 BTC to the wallet address that was created for you. If the payment is confirmed the decryption key will be sent to your computer and the Locker software will automatically start the decrypting process. We have absolutely no interest in keeping your files encrypted forever.
You can still safely use your computer, no new files will be encrypted and no malware will be installed. When the files are encrypted Locker v1.20 will automatically uninstall itself.
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When you see such a pop-up window, then your computer is infected with Locker v1.20. In recent days, Locker ransomware seems to have become more and more rampant. And what is more alarming is that there are many active variants of Locker including Locker v3.30, Locker v5.52, Locker v1.7, Locker v1.20, Locker v4.55, v4.81 and Locker v2.60. Anyway, whatever version you got infected, it is the same ransomware. Do not know how to remove locker ransomware variants like Locker v1.20, you are welcomed to read this post to get effective removal support.