Learning the hard way - AVG
I used AVG Free for several years, and got an email a year ago December notifying me that an update was available. It looked EXACTLY like ones I had received from them in the past, so I proceeded to run the update. After rebooting, I experienced a blue screen failure and my entire system was corrupted by a root-kit virus, destroying the zero sector of the hard drive and rendering the computer useless. So, my warning is similar to others: do not trust anyone or anything and do not run an update from one of these notifications. I have since gone straight to the company's website to first verify whether there is in fact an updated version of the software available. Only after I have confirmed this, and have created a complete system backup, do I run the update. And use a backup service such as BackBlaze or Carbonite to save at least your data, music, photos, etc. It is cheap insurance. Call me paranoid if you want, but this is the only way to protect yourself from the sob's out there who have nothing better to do than to try making the rest of ours lives miserable.