As an administrator, you may need to manually update the OAB files on the mailbox server when you need a new address to appear sooner than the next scheduled update.
Or perhaps you need to troubleshoot why a new address is not appearing in the OAB.
You will then be presented with a warning dialog box informing you that the process can take several minutes, which depends largely on the size of your infrastructure.
Then, in the top pane select the particular mailbox server in question and with this server selected, choose the Manage Diagnostics Logging Properties… Doing so will bring up the Manage Diagnostics Logging Properties wizard and on the opening screen scroll down until you find the MSExchange SA entry, which represents the Microsoft Exchange System Attendant service.
Expand this entry and select the OAL Generator category, which itself represents the offline address list generator process of the system attendant.
You may remember from part one of this article series that the mailbox server LABMBX is currently configured to generate the OAB data; you can confirm this by examining the Server attribute in Figure 5 back in part one; the Server attribute is the second attribute listed from the top.
On the server LABMBX, it is possible to navigate to the \Program Files\Microsoft\Exchange Server\V14\Exchange OAB folder to view the actual OAB files as you can see in Figure 6.
If you have not seen Dave’s blog before then I’d highly recommend that you bookmark it now, as it is contains a wealth of information not only on topics like the OAB, but also areas such as address list segregation.
As we have already seen in part one of this article, the OAB update is scheduled to occur once per day at 5am by default.
Manually updating the OAB can be achieved either via the Exchange Management Console or via the Exchange Management Shell.
In the Exchange Management Console, simply right-click the Offline Address Book object as seen in Figure 1 in part one of this article and choose the Update option.
The error events logged in the event log will help you to diagnose if any particular mailbox is not appearing in the OAB.
For example, consider Figure 9 where you can see that a particular mailbox is not appearing in the OAB due to an invalid SMTP address issue.
You can also see that the folder contains many OAB files that have filename extension of . These files contain the OAB information that will be downloaded by the Outlook client. LZX extension is derived from the fact that the files are compressed using the LZX compression algorithm. LZX file names shown in Figure 6 have the string “lng” in them, followed by a four-digit hexadecimal value.