Virtual hosting means that your site will be on a shared server.  Your mailbox name must be unique, not only on your site, but on the shared server.  Therefore, if you request a mailbox called bob@yourdomain.com, and there is already a mailbox on the shared server called bob@otherdomain.com, then we will need to alter your requested mailbox name so that it is unique on your shared server.  This is not as bad as it sounds... please read below.

If you request a mailbox name which already exists,  we will add a prefix to your requested mailbox name.  For example, if your domain is called yourdomain.com, we might call your mailbox yd-bob@yourdomain.com, but we would also set up a permanent alias for you, so that you could still use the simple email address bob@yourdomain.com.   That is, any mail sent to bob@yourdomain.com would be delivered to your yd-bob mailbox.  Furthermore, most email software will allow you to place bob@yourdomain.com in the From field of any outgoing mail messages, even though bob is not a real POP account.  So effectively, even if you are allocated the POP account yd-bob, you can still receive and send mail as  bob@yourdomain.com.

Having said that, you may prefer to choose mailbox names which are more likely to be unique on your shared server.  For example, bobjohnson@yourdomain.com would probably not need to be prefixed, because it is unlikely that there would be another bobjohnson on your shared server.

Finally, there are some mailbox names which are very common, including: webmaster, sales, info, support, and tech.  As stated above, there is no reason not to choose these mailbox names, but please be aware that they will certainly be prefixed, and that you will need to use your prefixed mailbox name when you retrieve your email from the server.