Q:

Email routing to local server instead of remote

I'm not an expert on servers but have identified an issue with my webhost and their email setup.  I've approached the hosting company about it, but being Hong Kong based a language barrier is preventing me from getting my issue across to them.  I'm hoping someone here can clarify the details and provide a solution for me to send them.
Our company has four domains hosted on a remote CentOS Linux server.  The email for our primary domain is dealt with via Windows Live Admin Center, the remaining domains have not required any emails until now.  We are trying to setup up forwarders so that we can have more brand focussed addresses (such as info@brand1.com, careers@brand2.com) redirected to our existing Windows Live setup.
However the forwarders fail everytime.  I can successfully forward to any valid domain email address apart from the Windows Live domain.  I can only assume its trying to deliver it locally instead and failing as a result.
Is there a simple setting somewhere that deals with this that I can simply point the webhosts to?

A:

If it is really just the domains hostet by the Hong Kong hoster, then all they have to do is make sure the MX-records point to the right mail server (which can be the same for all of your domains). It is then the duty of your mail server admin (maybe thats you) to make sure the mail server accepts emails for all of your domains.

