In your shoes, whether I did or did not have a proper data backup, I would still pull the storage drives. Set these aside for the day that some really bright soul provides decryption for this particular nasty. Then buy new drives and install operating system and programs fresh. If you have backup, restore only data files - as there is a chance that the ransomware came in a 'sleeping stealth' package.
It is a ransomware virus. Try this method to recover the files, I am not sure it will work or not but you can give it a try. First perform a system restore once it is complete download a malware removal tool & eliminate remaining .lokd ransomware files. After that windows previous version & try to restore the files. Hope this helps