I don't want to start using Avira but please help me, tell me what to do. Thanx!
Well why so paranoid? What you CAN do is don't use Firefox in Sandboxie. Vlk basicly answered your question with his question. I understand that we all have a strong need to be protected from viruses as good as possible, but some ways obviously don't work and that's by design! Sandboxing a browser is already a huge security improvement, the whole point about doing it (talking only about viruses) is that a malware etc. won't affect the rest of your system. The double protection with an antivirus on your host is of course a good and usefull thing, but you can't expect this software to compromise an other security software (Sandboxie) to be even better protected. If that was so easy to do by an antivirus application it would render the whole sandboxing product useless! That's why avast! (at least in my expectation) won't be able to get script shield working for Google's Chrome either, because that browser uses sandboxing technology out-of-the-box and was designed to be safe and secure. There were only 2 succesfull exploits written by now that made it possible to break out of the sandbox of Chrome and those were coded by absolute specialist from for example Vupen (
www.vupen.com), a company that makes money by selling exploits to interests from famous products. We ain't talking about some freaky hackers or amateurs that make viruses with toolkit's or some garbage here! Those exploits took weeks to write and your usual malware is not nearly as complicated and dangerous.
Maybe you reconsider your strategy and try to relax a little about your security. This post is not intended to offend you, just to help you understand properly about security measures.