Due to various synching schedules, it can take up to 48 hours before you could actually see a change in Outlook after a modification has been made on the Exchange server or in Active Directory.In this guide, the relevant timings are explained and instructions are given in how you can directly force an update and resync, which can be very handy when troubleshooting or when you work in an Exchange environment which sees a lot of user mailbox mutations.
The command for the manual update procedure can be found here: Outlook will automatically download updates only unless the size of the changes is larger than 12.5% (one-eighth) of the total OAB size.
In that case the whole OAB is being downloaded again.
OAB Update schedule To change the OAB Update Schedule via the Exchange Management Console: Organization Configuration-Rather than changing the default schedule, you can also force an update and redistribution of the Offline Address Book.
This is great for testing or when it is important that changes are published immediately (note that users must still update the OAB manually or wait a OAB sync interval to see the changes).
Use Cached Exchange Mode but without OABTo always work with the Online Address Book, even when you have Cached Exchange Mode enabled, you can set the following Registry key and value.
Key: All Users or any other object type such as All Contacts, All Groups or All Rooms.
Renaming just a single or some of the files will result in an OAB corruption. A benefit of manually deleting the oab-file is that before they are being re-downloaded, you are working with the Online Address Book.
When you find things working correctly for you now but not anymore after the oab-file were redownloaded, you know that the issue is with the oab-files on the server and not on the client or the Address Book configuration in general.
When you update an Offline Address Book on the Exchange server via the Exchange Management Console or the Exchange Management Shell, one would suspect that updating the Outlook client after that would directly get you this fully up-to-date copy. After the OAB gets updated on Exchange, it still needs to distributed to the web services first, even in a single server environment.
The process of updating and distributing the OAB is achieved by the following two schedules.
In a later section, it is explained how to modify this.