All email sent to mailboxes at your domain (e.g. joe@ mydomain.com), is routed to the mail server for that domain. Usually this is the same server that hosts your website, although sometimes clients have dedicated third party mail servers (e.g. a local Microsoft Exchange Mail Server). So when an email is sent to email@example.com, the internet routing tables look up the correct Mail Server on record for the domain mydomain.com and then send the mail to that server.
SWITCHING THE DOMAIN
When you switch your domain to a new server, you are essentially telling the internet routing tables to direct all traffic to the new server (this includes mail traffic, unless specifically redirected to another location manually). This is accomplished by logging into your Domain Registrar account (e.g. Network Solutions, Dotster, Godaddy, etc) and updating the DNS information to point traffic to our servers.
However, the internet has no centralized control system and it can take up to 72 hours for all the independent routing tables to update their information (as they see fit). Usually it happens within a few minutes to a couple hours, but there may be a period of time when some emails go to the old server and some emails go to the new server. In order to make sure you don't miss any emails, you will need to find a way to check both the old and new servers for a period of time.
BEFORE YOU SWITCH THE DOMAIN
Before you switch your domain to point to your new server there are several things you need to do. It is very important that these steps are coordinated properly, or else people will have trouble checking their mail. Our responsibility is limited to making sure that the mail server is functioning properly. It is the clients responsibility to ensure that the switch is handled appropriately internally within their own organization.
CHANGING YOUR MAIL PROGRAM SETTINGS
Please refer to the articles below for general setup instructions for your mail program. If you use another program, the principles are the same. If you are switching your domain from another server, remember that it may take a couple hours for traffic to direct to the new server. Be patient.
SUGGESTIONS FOR CHECKING BOTH OLD AND NEW SERVERS
Because there is a period of time when email may be going to both your old and new servers, after a domain is switched to point to a new server, you will need to make sure to check your old server at least one last time before abandoning it. The best way to do this is to use your old server's "Webmail" access. Usually you can access this through an alternative domain (e.g. the domain of your old host, or through your old hosts control panel, etc). It's important to find an alternative domain access because your domain will likely be pointing to our new server at this point. If you can access your email through a webmail interface, you can read and forward anything that happens to come in to the old server.
Alternatively, if there is no webmail access at your old host, you can usually setup a temporary account on your mail program and point it to your host's mail server. Instead of using your mail server url, e.g. mail.mydomain.com, you would use your old host's domain, e.g. mail.myhost.com and usually this will require that your username includes your full domain, e.g. instead of username of "joe" you would use "firstname.lastname@example.org".
Either way you should contact your old hosting company to ask them for details and help regarding how to check mail on their server, when your domain name points to another server.
If you are having trouble setting up your local mail program to access the mail on your new server hosted with Gutensite, you can always check email via your webmail interface.