The following document explains how to configure directory search in Outlook desktop client.
Click on the File tab.
Click on Account Settings, then "Add and remove accounts or change existing connection settings."
A screen will appear, select the Address Books tab, the tab farthest to the right.
Then click New...
Select Internet Directory Service (LDAP)
Then click Next
In the Sever Name field, type: ldap.services.wisc.edu
Then click on More settings...
You will see a pop up that says "You must restart Outlook for these changes to take effect."
Within Display Name, enter: ldap.services.wisc.edu
Then click on the Search tab.
Under Search Base, select Custom.
In this field, type: dc=wisc,dc=edu
Then click OK
Now you should be back on the screen called Directory Service (LDAP) Settings
You should see the following screen:
Click Close in the Directories and Address Books window
You will need to exit and restart Outlook before you can use LDAP.
Click on the File tab
Then click Exit
Click on Address Book
In the Tools menu, click Options
Make sure Custom is selected. Then click on ldap.services.wisc.edu to select it, and use the arrow to the right to move it to the top of the list.
Then, under "When opening the address book, show this address list first:" select ldap.services.wisc.edu
Then click OK
When you relaunch Outlook, you should be able to search the LDAP directory!