Security, Cryptolocker, Ransomware, Malware

Cryptolocker/Ransomware scams involve a type of malware that infects computers and restricts users' access to their files or threatens the permanent destruction of their information unless a ransom is paid. Once Ransomware launches on your machine, it is nearly impossible to access your files.

For future reference you will want to back up your files to cloud storage service that keeps a history or archive of your files. Such options include:

U of I Box : http://box.illinois.edu/
Google Drive: https://drive.google.com/drive/my-drive
Microsoft OneDrive: https://onedrive.live.com/about/en-us/

What can you do to avoid this in the future? Be vigilant. Know what 'normal' is like on your computer so if anything goes wrong you'll recognize it sooner. Also, don't click suspicious links or attachments, avoid using email for file sharing.

More detailed info from Microsoft can be found here.