Microsoft Outlook has many new features and enhancements that are related to the offline address book. By default, Outlook uses a cached mode configuration. Dear EE Well, the title kinda says it all. I got a hybrid setup with Exchange 2010 and Office 365. If I create a distribution group on premise it does sync to Office 365 and is available in the global address list but for some reason, the offline address book is not updating. When you have Cached Exchange Mode enabled, Outlook by will by default cache the main Global Address List as well. This is called the Offline Address Book and is being generated on the Exchange server. I noticed that a new email address was not showing up in the global address list in Outlook 2010 for a few executives. Some initial investigation resulted in pointing the finger at the offline address book. Updating the Global Address Book in Outlook on Windows. The Global Address Book (GAL) is a directory of available contact information for CUMC, NYPH and Columbia University faculty, staff and students. We had the same issue with Exchange 2007 and Exchange 2013. Our GAL and OAB were healthy and updating for Outlook clients in cached mode BUT numerous other address lists such as those we created for each location and division were not updating. Hi Michael, Sorry for a late response, I did not see that your comment was pending approval. The idea behind the offline address book is that a rich client, like Microsoft Outlook 2013 for example, could download it and allow the user to compose/address emails while working offline. I have few suggestions for you to check this. 1. If you see the name in address book on one user machine and not on other, then it is the problem with user outlook profile. While you may have sorted your Contacts folder the way you want it to, the Address Book in Outlook has its own sorting mechanism. The separation can be quite confusing some times and the options which control the sorting order aren’t all located in the same location either, which can make things even more confusing. If you want the ability to use a shared contact folder as an address book, vote for the suggestion in Outlook Uservoice at Add the feature to show shared contacts in the user’s Address Book in Outlook 2016.If the suggestion gets enough votes, Microsoft will consider adding it to a future version.