All, By the end of this year my company is expanding to approx 30 users, currently we are using exchange 2000 SPA on a Windows 2000 SPA Domain Controller, Reading Microsoft's installation guides / opinion on Exchange 2000 that you should not really use Exchange on a DC, unless you are only a small number of users (less than 10) you should ideally use a separate server for all your exchange needs. But to do this I need to convince my MD! Can anybody point me in the right direction to advantages / disadvantages of using exchange server on a DC with 30 user (or above 10) and using exchange on a separate box. Any opinion or sites / books to read would be grateful Simon Whale ----------------------------------------------------------------------- This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify admin@xxxxxxxxxxxxxxx The views expressed in this email are those of the individual and not necessarily those of UK Data IT This footnote also confirms that this email message has been swept by SOPHOS AV for the presence of computer viruses.