If you are using older ESET Antivirus products (e.g. v6.x) on Amazon Web Services (EC2) Elastic Cloud Compute (EC2) Windows instances (which we use for Spira and KronoDesk) you may not be able to easily upgrade to the latest version of ESET 7.x because ESET 6.5 will block its own un-installation. We have a solution that worked for us that we'd like to share.