======Handling mail for multiple incoming domains======

VPOP3 can easily handle mail for several incoming domains.

Exactly how you do it depends on the exact situation.

=====All domains are 'aliases'======

If the domains are aliases of each other, for instance, you have 'mycompany.com' and 'mycompany.org', both of which are the same, so each address at mycompany.com also exists at mycompany.org, and the emails go to the same people regardless of which domain is used, then you simply configure the domains in the mail collector(s) accordingly, and don't need to do anything else

For instance, if you have one catch-all POP3 mailbox at the ISP which collects mail for both domains, you would simply put both domains into the **Accepted Domains** box for that collector in VPOP3, separated by a semicolon

{{:how_to:multipledomains1.png?nolink|}}

Or, if you have several catch-all POP3 mailboxes at the ISP, simply create multiple collectors in VPOP3, each with the appropriate **Accepted Domains** setting

Or, if you have an incoming SMTP feed, then put all the domains into the **Local Domains** box, separated by semicolons.

=====All domains are different======

If your domains are different, so that, for instance, mail for **mike@company1.com** has to be kept separate from mail for **mike@company2.com**, then use [[Reference:mappings|Mappings]]

In this case, you may create users called **mike1** and **mike2**, then create two Mappings: **mike@company1.com -> mike1**, and **mike@company2.com -> mike2**. (The actual names of the users don't matter, you could use 'mike.company1', or whatever is easier for you)

====Preventing normal <username>@<domain> -> <username> distribution====

With the normal settings, this will work for cases where most users are the same on both domains, but where there are a few exceptions. Also, in this example, sending a message to **mike1@company2.com** would still go to the **mike1** user, even though 'mike1' should only be associated with company1. To stop this happening, go to the Mail Collector, go to the **POP3 Routing -> Configure Routing Options** window, then check the **Disable default user -> user mappings** box, and press Submit.

{{:how_to:multipledomains2.png?nolink|}}

Once you have done that you //MUST// create mappings for all the email addresses you use, as VPOP3 won't assume that each user has a 'username@accepted-domain' address as it normally does.