I've been trying out NOD32 for a week or so and have noticed the following issue: I use Thunderbird which checks 3 POP3 accounts from my ISP. In around 30% of my incoming emails, there is *no* NOD32 certification visible ("this mail has been checked by ESET........"). However, all emails that I send from one of my accounts to the other contain the certification. I suspect that NOD32 is indeed checking all of my emails but something in the emails is preventing the display of the ESET certification. Does anybody know what is causing this? TIA!