When the value is set to 0, Outlook will use 16 to prevent a “divide by 0” error.If the key name doesn’t exist, Outlook uses a value of 8.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).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.Full OAB download threshold To modify the threshold at which Outlook will download the full OAB rather than the incremental update, you can set the following Registry value Key: As the value, set at which relative size a full OAB download should take place rather than an incremental update.For instance, setting the value to 4 will trigger a full download when the incremental update is larger than one-fourth the size of the full OAB.
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.
Each time we open Outlook, the synchronization process start and stop in the middle, for some reason, we cannot figure. The less good news is that there are many grounds for this issue, and there is no “magic” solution that will help us to solve the synchronization problem in “one click.” In this article, we review the cases and the troubleshooting steps for mitigating optional causes for Outlook synchronization problems in Office 365 environment and review the specific charters of Outlook and Exchange Online environment.
I know that this article could consider as “long and tedious” but the Murphy law dictates that: most of the Outlook synchronization problem accrues to “VIP Users,” that usually demand a solution!
You’ll find the following 6 oab-files in this location which make up the full Offline Address Book: If you are still using Outlook 2002/XP or previous, the file names won’t have a “u” in front of their name.
You’ll have to rename them all to or, in the case of Outlook 2010 or Outlook 2013, rename the folder containing the oab-files to to reset the local Offline Address Book.