Data Security
A member of another forum recently contacted me RE CryptoWall. At the moment there's not a lot that can definitely be done because of the nature of the encryption.
It's predecessor, Cryptolocker, has been broken and keys are available - they MAY be able to help with Cryptowall but don't count on it.
Now, the attack vector is via email and file attachment. Of course the ideal is to delete all questionable emails without opening them.
This sounds good in theory, but most people who use fat email clients like Outlook also set it to display the currently highlighted email - this must open the email to do so and will execute any code that opening an email will do - you can get infected REALLY easily this way.
My advice is TURN OFF preview - yes, I know it's inconvenient but it's a lot less inconvenient than losing your data, or worse, having it encrypted and an extortion notice to decrypt - how bad is it knowing your data is there but you can't get it because some mongrel has encrypted it.