We have a client that has two companies operating from the same Windows Domain and the same Exchange 2007 server. Some of the employees work for both companies, and have email@companyA.com and email@companyB.com and need to be able to select which domain they are sending from to maintain the external appearance of seperation between the companies. Normally, this could be accomplished by making the from field visible in the Outlook message composition window and entering the appropriate address there, however Exchange 2007 recognizes this as an email address associated with User X and automatically substitues the default email address before sending the message out, so even if User X has manually set the from address to email@companyB.com, if his default email address is set to email@coompanyA.com, then the recipient sees email@companyA.com as the reply address. Any suggestions to correct this issue are appreciated.Thanks,Matt

Exchange 2007 doesn't have ability to choose secondary smtp address in from field while sending mail, however there are some workarounds and third party tools available... Check below thread to see detailed discussion and various methods available... http://social.technet.microsoft.com/Forums/en-US/exchangesvradmin/thread/1040e63c-75e4-4824-b92b-931e47086bb3Amit Tank | MVP Exchange Server | MCITP: EMA | MCSA: M | http://ExchangeShare.WordPress.com