Hello, Currently we are running Exchange 2003 which obviously came with the Outlook 2003 license in it. We are looking to update to Exchange 2010. The question is that since we are not getting rid of our CALs from Exchange 2003 can we still use the Outlook part of that CAL and continue using Outlook 2003 to connect to Exchange 2010? We are aware that we still would need Exchange 2010 CALs.

No one on this site is authorised to answer questions on licencing. You will need to ask Microsoft for the definitive answer. My understanding is that you will be able to use Outlook 2003 for existing licences only. If you purchase additional licences for Exchange 2010 (so you have 30 Exchange 2003 CALs but buy 50 Exchange 2010 CALs) then the additional licences would not be licenced for Outlook. Are you not using Microsoft Office then? Outlook 2003 is a bit long in the tooth now, for the full feature-set of Exchange 2010 you should really consider Outlook 2007 or 2010. However all of the above is no use to you, as I am not Microsoft. Call the Microsoft licencing hotline and ask them. Get it in writing. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Hi, For question about license , I suggest you contact Microsoft licensing specialists, they can help you on this issue: Phone Support: http://www.microsoft.com/licensing/pur/phone.aspx Website: http://www.microsoft.com/licensing/index/worldwide.mspx Thanks, Evan Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.