In general, Outlook will automatically update the Offline Address Book (OAB) for Exchange accounts once every 24 hours.
When it doesn't or when you want to make sure you do have the latest OAB available, you can manually trigger an update from within Outlook as well.
If the update mechanism appears to be broken for you, it could be because of a corruption in your OAB or in your mail profile.
In this case, you can completely reset it by deleting the files making up the OAB or by recreating your mail profile.
Update OAB from within Outlook
Rather than waiting 24 hours for Outlook to update the Offline Address Book on its own, you can force an update via the Send/Receive menu button.
Outlook 2007 and previous goto Tools-> Send/Receive-> Download Address Book…
Outlook 2010 and Outlook 2013 tab: Send/Receive> Send/Receive Groups-> Download Address Book…
You can disable the option “Download changes since last Send/Receive” to make sure you get a complete fresh copy of the OAB but this could take longer to download. It is recommended to leave the option “Full Details” enabled. In Outlook 2013, you’ll find that this option is no longer available as full details are also used to build the Contact Card.
Delete the OAB files
Another way to make sure that you get a fresh copy of the OAB is by renaming the oab-files to .old when Outlook is closed.
They are stored in the following location:
Windows XP - C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Outlook\
Windows Vista, Windows 7, Windows 8 C:\Users\%username%\AppData\Local\Microsoft\Outlook
You can paste the path mentioned above in the Address Bar of Explorer to quickly open the location. When you are using Outlook 2010 or Outlook 2013, you’ll find a folder called Offline Address Books which itself holds subfolders with named after Account GUIDs.
When you have multiple Exchange accounts configured, you’ll find a folder for each account that you have. The quickest and most thorough method is to simply rename the Offline Address Books folder by appending .old behind it. When you use Outlook 2007 or previous, you’ll have to rename the individual oab-files instead. There are 6 of them: uanrdex.oab ubrowse.oab udetails.oab updndex.oab urdndex.oab utmplsts.oab After deleting the files, make sure you trigger a manual update from within Outlook as described above.
Recreating the mail profile
If you are still having issues with your OAB afterwards or if the files aren’t being recreated after a manual update, it is very likely that your OAB issues are rooted deeper in your mail profile. In that case, it is recommended to recreate your mail profile.