I have successfully changed the last name of a user in AD however I am unsure how to change the name in Exchange. When they send e-mail it still uses the previous name. Also when in Outlook the previous name is displayed at the top of the folder list. How do I make it so the new name is reflected in the users e-mail.

Suggest you to make sure that you have followed all steps explained here, including display name changes... User Name Changes http://www.amset.info/exchange/usernamechange.aspAmit Tank | MVP Exchange Server | MCITP: EMA | MCSA: M | http://ExchangeShare.WordPress.com

Added to Amit... Just rename the account in Active Directory. Keep the existing account+mailbox, saves you a lot of headaches! Just right-click the account in AD, select Rename and follow the wizard. After the wizard is complete, the user's email addresses will be changed automatically by Exchange 2007 to comply with your company's addressing policy, so you'll need to manually add the old e-mail address to the mailbox, at least until the user has communicated the name change to all his contacts.Reference: http://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/Q_23650525.html

In addition to what the others wrote, a lot of the time the user will complain that their name still displays as their old name in Outlook (where it shows Mailbox - Name). If the user does make a complaint about this, you can have the user do an Outlook Repair or close out of outlook and go into the mail control panel applet and change their name and then click Check Name. This should resolve that complaint.MVP | MCITP: Enterprise Messaging Administrator | MCTS: OCS + Voice Specialization