Hi All Pro's Following the separation of companies i was asked to define two separate mail servers with the same domain name @ domain.com. the companies should be cut off completely. There is no sharing of information between companies and no sharing users. MX record are set to different priority, from what that I know,the two companies can still set up the exchange server to access each other mail account, the CEO or any user who is using the Competitor company. The two companies do not want to change the domain so it was decided on this option. How can I prevent the above problem and make an absolute disconnect between the companies with unchanged the Domain Name. clarify: the 2 companise have one single domain name with One server for each company, the 2 companise want to keep the mail address without sharing information, that is the agreement between the two companise without change the domain name or add a new domain name. (They fought for this domain name in court and that is the decision) there is any service or third party that can manage the mail address with reference to a specific server? Any ideas?

There is no concept in DNS to sort this out. If you set the MX records to both servers then it will be pot luck on whether the email is delivered correctly or not. DNS and MX records have no connection between users. Both servers have to know who is on the other server, otherwise you will have to deliver email to one server and have email for another server forwarded to the other. This then has the issue of email to non-existent recipients bouncing, going through one of the servers (which the other may not like etc). Another option would be a third server that holds a list of all users and then forwards the messages across. I am not aware of any service that does this specifically. One of the hosted antispam services might do it, but it is still going to mean that a list of users on both servers is held by some service somewhere, which coordination is going to be required. I wrote this some time ago: http://www.amset.info/exchange/twositesonedomain.asp However as you will note it requires the servers to know of each other. Unfortunately this is a court decision made without any technical input which is going to be almost impossible to fulfil if they will not cooperate. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Have you tried to explore a three forest structure? with the two companies having two seperate AD forests with a nuetral exchange forest in the middle? This way the exchange servers would have access to two totally seperate users lists while keeping the same e-mail domain. I think having seperate forests for AD & exchange is supported, so why not with 3 forests, exchange servers being located in the middle nuetral forest. I think each AD forest will require trust with the exchange forest but not necessarily with each other. Perhaps this can be useful in your scenario, as I suspect the dispute is only on the public e-mail domain name, not the totally internal AD domains. Hard Stone.