I just set up MSIE 3.02a (slightly older version) about a half-hour ago and
was able to get into the mail program just fine without being connected.
When you run the Internet Mail program, it first asks for a username and
login--this is to determine which mail profile to bring up (Internet Mail
for Windows 3.1x supports multiple profiles). It will then bring up the
"connect to" window displaying whatever username/password is used to
connect to the internet. Just hit close. Now that you're in the mail
program under the profile for which you originally logged into mail as,
just create the new mail or read old mail... When it's ready to be sent,
just click on "Send and receive." If it tries connecting then and you
don't want it to, just hit Close on the connect-to window again. It'll
drop the mail in the outbox, so that the next time you go online and hit
send/receive, it'll send the mail off.