You can easily get by with a Free AV or even Microsoft Windows Defender in 8.1.lol That's why I'm to get an A/V license here...
Look, I did it yesterday already lolThanks for sharing your configuration Mr.X. I've only heard excellent things about appguard.
As to the warning our member/friend, Moose, mentioned about AV compatibility, I can confirm both ESET & AVAST! allow funtionality with Sandboxie.
For winning an AV key, you've certainly come to the right place. I'd used Avira free to protect our old XP system before it retiring it in dry dock, and it worked fine alongside Sandboxie. In fact, unless you've already entered, follow me now to win one of 15 keys for Avira Pro 2015! You'll find it's link near the top of the page.