Nope, the ".com", is part of the "domain-name", and could be any number of variations, such as: ".org", ".net", ".edu", ".gov", ".mil". In this case it is actually ".com", but I didn't want to include the full email address in my question. The part that wikitree is rejecting is the "period", between the"g" and "simon". that is acceptable according tto Internet Standards, and works everywhere except on wikitree.