Regularly backup your data, and make sure the backups are not connected to the computers and networks they are backing up. Most ransomware variants can encrypt files on any attached drives or network files that are also accessible to the host machine (including cloud hosting and cloud-based backups if those passwords are stored on the machine). Bleepingcomputer’s Lawrence Abrams just published this protect against ransomware a nice primer called How to Protect and Harden a Computer Against Ransomware.
Many companies are now selling products that claim to block ransomware attacks. Those claims are beyond the scope of this article, but don’t be lulled into thinking these products will always protect you.
Even products that could somehow block all ransomware attacks can’t prevent the biggest reason that ransomware attacks succeed: They trick victims into taking an action that inadvertently undermines the security of their device — be it a smart phone, tablet or desktop computer.
This usually involves clicking a link or downloading and opening a file that arrives in an email or instant message. In either case, it is an action that opens the door to the attacker to download and install malware.
Remember my Three Rules of Online Security:
1: If you didn’t go looking for it, don’t install it.
2: If you installed it, update it.
3: If you no longer need it (or, if it’s become too big of a security risk) get rid of it.
Source of Content KrebsonSecurity.com-before you pay