How to prove that an email has been sent?
I need an advice regarding something technical that has some relation to some legal misunderstanding. It boils down to this:
Can a mail sent from gmail.com be "faked"?
What do I mean? If I say, sent an email to some person, and have it still (the email) in my Sent Mail "folder", could I have faked it somehow? I just need to know roughly, because that person claims that he never received the mail from me (which is irrelevant) because I have not sent it (which is relevant).
P.S. I have no idea whether this is more appropriate here or on webapps. I am interested in this case in gmail.com because I have a mail there, but the question stands in general. Were I to have mail on some other server, and were I to use Outlook for example, would it be possible then?