Jessica,
Do you have a firewall in front of the smartermail server ?
If so the proper ports have to be open.
Are you using any other control panels with Smartermail ? are you possibly using Plesk ?
Every time i set up a new domain on our server, One of those two sets the binding access of smartermail as"webmail.domain.com"
Where I was expecting it to set as "mail.domain.com" instead (our old server used to set that)
It took me 3 days to realize that our new server server was setting it as "webmail."
www.HawaiianHope.org - Providing technology services to non profit organizations, homeless shelters, clean and sober houses and prisoner reentry programs. in 2018, in just one year, we gave away 1,000 Free Computers !