I have four Exchange servers across four sites. I've made updates to my Global Address List (GAL), but those updates are not replicating to all four sites. How can I fix this once and for all?
Any time you run into an Exchange Global Address List issue, the first place to investigate is the application event logs on the Exchange server that is generating your offline address book (OAB). There are too many event IDs to reference here, but most that are OAB generation-related should be resolved if you updated your Exchange server with the latest service pack and rollup.
You should also check that all four sites can communicate on port 25, in order to allow replication traffic to pass through. The easiest way to test this is to use an old Microsoft tool known as Portqry.exe. Once installed, use the command line to navigate to the directory that you installed the tool to and run the following command:
Portqry.exe -n <remote server name> -p tcp -e 25
If this is working properly, you should receive a "listening" response.
You should also make sure that the OAB references on each site's Exchange server are correct. This helps make sure that Outlook 2007 (and higher) clients using Web access for OAB updates point to the right location. This is located in the Exchange Management Console -> Server Configuration -> Client Access Server -> OAB tab.
Similarly, if your organization uses public folders, make sure that mailbox servers at each site are listed in the replication tab within public folder properties. They should be inherited by any child folders of the OAB public folder by default, but it's not always the case. Therefore, it's important to double check.
Remember, the slower your links are between the sites, the slower replication will be between servers. Thus, Exchange Global Address list updates will process slower as well. If you make a change to your organization and want to ensure that replication occurs immediately, you can force synchronization using the following Exchange Management Shell command:
Update-GlobalAddressList -identity "Default Global Address List "
About the author
Dave Leaver has worked in the IT industry for the last ten years as an IT support engineer. He currently works for an IT support company in Cheltenham, U.K., supporting more than 1,000 users and spanning more than 40 companies. Leaver specializes in Microsoft system migrations and Exchange Server. Leaver has also been a network administrator for the National Health Service and several large construction companies throughout the U.K.
This was first published in May 2013