The latest in a long string of ransomware infections now has mainstream media reporting on it.
As usual the best defence is not to click or open unexpected emails/attachments/links and be very careful when browsing the internet.
The main difference with this strain of ransomware is that once a single computer is infected it can then infect all other computers on the company network.
UNLESS Microsoft security patches have been installed.
Security patches are usually automatically installed, so please make sure you act on the Microsoft system tray notifications (near the clock bottom right of the screen) and reboot afterwards.
For anyone still running out of date software, Microsoft has taken the unusual step of releasing a patch for the obsolete Windows XP and Server 2003.
Links for WindowsXP and Server2003 patches