Global address not updating under Outlook cache mode

n cached mode, users will appear the next morning. Exchange rebuilds the Offline address book at 4am(i think). If you want to force a manual update..

Expand Recipients, click on Offline Address List. Right click on Default Offline Address List in the right pane. Click Rebuild. The Rebuild could take some time depending on how many users you have.

To get the new users to appear in outlook once the rebuild has been done: Open Outlook, Click Tools –> Send/Receive –> Download Address Book. Then place a check in Download Changes since last Send/Receive. Click OK. The new OAL will download.

Source: http://forums.msexchange.org/m_1800427039/mpage_1/key_/tm.htm#1800427039