So I have been having this issue where my users using outlook 2010/Exchange 2010 were unable to download the address book via the outlook client by going to "Send/Receive -> Send/receive group --> Download Address Book"
When they did that the dialog box would come up but it would just hang and sit there forever! The last thing I remember doing was that I had setup my owa re-direction using IIS from http to https for my internal users.
So after looking around it turned out that once I setup the re-direction I have to change the permissions on a web.config file stored under "C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\OAB"
So right click the "web.config" file under this location and go to Properties --> Security --> Edit --> Add --> Authenticated Users --> and give them Read and Execute Permission.
Click Ok a couple of times to accept the changes and then go back to your outlook client and close and re-open it and try downloading the "Address Book" and hopefully it should work! (Well it did for me!)