Recurring Conteban Trojan Warnings on External Drive: Document Infections and Scans Show No Threat

Hi, I recently have been getting a warning of conteban trojan from windows security. It says the threat is severe. So I click remove. Everything seems ok then I edit word doc which is kept on an extrernal portable drive and try to attach it to an email and I get the Arno g again that the document is infected with the trojan. So i remove again and download malware bytes and do a scan and it shows nothing? is it possible for portable drives to have a Trojan? I used windows defender to scan the drive and it says there is nothing but then when I make a new doc and try to attach it to email it says again that there is a Trojan and it deletes the document. i don’t understand what is going on with this. If I have windows defender and malware bytes both saying there is nothing so what is the issue with word docs?