OAB Download and BITS Service
I’ve recently stumbled upon a scenario related to downloading the offline address book which might cause confusion and hopefully this blog article will shed some light as to what is happening.
All users started to complain that they are unable to perform a download of the offline address book and they are hitting the following message in Outlook “Unknown Error 0x80070422”:
Naturally we’ve started the investigation by examining the OAB generation Server (that’s what you should first do and check that is working properly) and couldn’t find anything wrong or suspicious even after raising event logging for the MsExchangeSA/OALgenerator to expert.
Afterwards we examined the Client Access Servers, specifically the OAB Folders
<C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\OAB>
And could see that they were up-to-date with the generation server, meaning that the “file distribution service” on the CAS were doing their job to copy the files from the mailbox server.
Next we decided to decode the actual client error code 0x80070422 which translates to the following:
“The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.”
Following this we decided to check the services console on the outlook client machine and we could observe that the “Background Intelligence Transfer Service” was explicitly disabled via Group Policy.
If the Outlook Client was running in online mode, an attempt to download the OAB would result in the following error message: "An error occurred while opening the Microsoft Exchange Offline address book files on the Microsoft Exchange Server. See your administrator."
Note: Even if the BITS Service is stopped, Outlook would start it on demand when attempting to download the address book. Should the service be explicitly disabled, it would no longer be able to start on demand and fail thus throwing the error message “Unknown Error 0x80070422”
For more information see the following KB Articles:
https://support.microsoft.com/kb/2429946 How to troubleshoot the Outlook Offline Address Book in an Office 365 environment
https://technet.microsoft.com/en-us/library/bb232155(v=exchg.141).aspx Understanding Offline Address Books