I'd recommend you NOT buy this. We've had it for two months and we've found a number of issues. First, encrypted emails only actually show up at the intended recipients about 1/3 of the time. So, it has a common problem being flagged on other emails exchanges. Also, it conflicts with Office distribution lists and ultimately disables them. Add the fact that tech support never seems to know how to troubleshoot problems on this product. It's been a real headache.