JamesR

Which version of ESET is installed? If not on v7.x, you will want to upgrade to v7.x ASAP as it has Network Attack Protection which can block EternalBlue (MS17-010) and help prevent reinfection and assist in identifying IP addresses that are attacking computers on your network. This will also help you verify if this infection is spreading via a network exploit or not. From everything you have posted so far, I see no hard evidence of exploitation via MS17-010. Also, if you can provide logs using ELC (https://support.eset.com/kb3466/?locale=en_US&viewlocale=en_US) this can help identify what is occurring. When running ELC, please set the top drop down list to "Threat Detection".

I have replied directly to dandodds. I have been sick lately, but am feeling much better now.