Your anti-virus.....

If you're using Malwarebytes Anti-Malware, the free version has just been updated to a newer version, (1.60.1.1000) so when you do a manual update of its database it will also download and install its new update.

This is one of the best-rated free anti-virus products, and it works along with other security programs without problems, so if you'd like some additional protection, you can get it by clicking here.

However, my own favorite for excellent protection and features, including automatic updates which will audibly announce themselves upon arrival, is the one from Avast, version 6.0, available by clicking here. The free version has features you'd pay for in someone else's program, and it works very well. If you only want one anti-virus program, then this is my choice.

While on this subject, may I remind you that for 'zero-day protection' which means before your database could be updated, then download ThreatFire. It works by detecting suspicious behavior of malware, and doesn't rely on a database which may not be updated quickly enough. So with this and another regular anti-virus program, you're covered quite well. As they say, an ounce of prevention is worth a pound of cure.