I\'m trying to identify current user\'s name to make notes of who edited what like this:
r.setComment(\"Edit at \" + (new Date()) + \" by \" + Session.getA
I suppose you have this piece of code set to execute inside an onEdit function (or an on edit trigger).
If you are on a consumer account, Session.getActiveUser().getEmail() will return blank. It will return the email address only when both the author of the script and the user are on the same Google Apps domain.