We have 4 small sister (10- 15 employees per ) company and would like to have them all on the same Exchange server. I need help with detail step by step on how to setup 1 Exchange 2003/Windows Server 2003 with 4 separate company domain. They should NOT be able to see each other and would like to use RPC over HTTP. I tried following the following instructions but each company is still able to view each other in the address book. I'm sure it's just something simple that I am doing incorrectly.
Also, I would like to keep each company on there own mail storage too and tighten any security hole from SPAM, SPOOFING and etc. One more thing can I use 1 SSL certificate for all 4 companies?