Thunderbird reports ESS Add-On is NOT COMPATIBLE in ESET NOD32 Antivirus Posted September 30, 2014 No, I'm just a user. And maybe I have to say that you could manually remove it - but you would have to do it in a very aggressive and extraordinary way and so I can't guarantee that ESET and Thunderbird are still working after this. You do this at your own risk! The files for the add-on are saved in %programfiles%\ESET\ESET Smart Security\Mozilla Thunderbird or %programfiles%\ESET\ESET NOD32\Mozilla Thunderbird. So is is possible to deactivate self-protection of ESET and delete this files. But it is really not recommend! Just let the few bytes there. They aren't disturbing and so I see no reason to delete them. You are wrong that they cause no harm. Did you miss my last post about how it causes a very long pause every time Thunderbird updates, because it is searching for an update to the ESET plugin? This causes no end of support calls to me whenever a Thunderbird update occurs. But, no worries... I had opened a case with ESET, and they just replied, and as soon as I saw where they were going with how to remove it, I realized I could have done it all along with the policy editor (we are an enterprise customer and have the RAS/RAC for managing our clients).