wrote:
As it turns out, I'm really looking for the outgoing mail
and not the incoming POP3 as I initially stated. My own
address is smtp.charter.net so I would want the cell to
reflect "smtp.charter.net". But if someone else opens my
file on a different computer with a different outgoing
address, I need the file to post their address. Again,
is this possible?

Probably. I Googled "excel smtp server" without quotes and got a number of
hits. Most are not useful insofar they require that you provide the SMTP
server name, which of is the opposite of what you want, of course.

I did find this thread: http://www.excelbanter.com/showthread.php?t=391054.
It seems to be directly "on point". But I did not see a usable conclusion.

The points a

1. You might find what you need by reviewing Google hits in more detail that
I have time to do.

2. You might get a more-informed response by posting at excelbanter.com.

The question I would ask is: why do you need this?

I wonder if the real problem you want to solve does not need the SMTP server
at all. You are merely over-thinking the problem. Specifically, if the
"real" problem is that you want to be able to send to a configured SMTP
server, one of the Google hits might help you with that. (But I did not
study them in enough detail to say "yes" with impunity.)

But it is a rhetorical question. I suspect I cannot help you, even though I
fully understand the question and the issues.

Good luck!