We are currently experiencing an issue with Outlook 2013 in our Exchange 2007 environment.
When we view a contact card no GAL information is shown, we have found that turning of cached mode resolves this issue but we cannot use this as a permanent solution.
Upon researching this bug I have found the issue documented in the following forum http://social.technet.microsoft.com/Forums/en-US/officeitpro/thread/d0daf5a3-1711-4575-bfd0-a0dda40b81ce and have discovered Microsoft later released KB2768342 back in April to solve the issue but later withdrew this as it caused more problems. http://support.microsoft.com/kb/2768342
We have also found that deleting the local copy of the address book fixes the issue for a short period of time until it is rebuilt.
(%userprofile%\AppData\Local\Microsoft\Outlook\Offline Address Books)