I work in a small office (6 people) and we recently started training a new person, who shares a first name with another worker who has been in the office for the last ~5 years (let's call them "John").
It happens to be the case that the new trainee has a surname which is also used as a first name (e.g. his full name is something like "John Scott"), and he's often referred to by friends etc. by his surname (i.e. they call him "Scott" and he introduces himself sometimes as "Scott" and doesn't have a problem with this). The first John has the email address "john@[domain].com" and we now have to set up a new email address for the second John. He says he's happy to have "scott@[domain].com" but obviously he'll be signing his messages with his full name "John Scott". I'm arguing that his email address should probably be "johns@[domain].com" as this is how I've seen it done before. Others in the office argue that this way will cause more confusion.
Basically I'm trying to remove confusion in terms of when people call up and ask for "John", and people emailing us and getting addresses mixed up. What's likely to be the best way to go in terms of how he introduces himself, and the email address and signature he uses?