To update your address book manually to get all new accounts do the following:
In the main Outlook window click on “Send/Receive” in the ribbon:
On the “Send/Receive” ribbon click on “Send/Receive Groups”, then click on “Download Address Book”:
In the “Offline Address Book” window keep the defaults and press OK to download a fresh copy of the Outlook Address Book:
You should then be able to follow the instructions for adding a shared calendar to Outlook 2010 in this post.