A Cautionary Tale

Having recently acquired a new phone, I was copying a few files from the old one to the new one. I noticed a video from the old one was in the .3Gpp format. I wanted to convert it to MP4 or WMV to make it easier to play on different devices.
I googled for video converters and download one that seemed to be coming from a normally reliable website. What a mistake I made.

After installing this converter, it immediately took over IE9 and Firefox and installed weird toolbars and started throwing up dialogue boxes offering to fix the problem if i gave them my details.

This is the first virus I've had in 15 years or more and neither of the AV progs I have detected it on the way in. After running full scans with both of them they still did not detect it. I ended up going through the Registry and deleteing every entry I could find associated with the virus. After many tries and rebooots I finally got back to the state where my browsers were once again clean and I could find no trace of the virus in the registry
Fortunately the computer in question is not my main office computer, so none of my more sensitive details could have been compromised. I am still a bit concerned the infected computer may still contain some hidden code, so I will not be using itfor any business that involves anything to do with financial transactions for the forseeable future.

A close call, but it could happen to any of us. Eternal vigilance is the price of security. It also helps if you are not an idiot and download some questionable software.