Disable shared mailbox caching OST

Command Line:

Outlook 2013:



Outlook 2016:



Group Policy:

  1. Download the following file from the Microsoft Download Center:
  2. Extract the admintemplates_32bit.exe or admintemplates_64bit.exe file to a folder on your disk.
  3. Copy the file appropriate to your version of Outlook to the C:\Windows\PolicyDefinitions folder.
    Office 2016: Outlk16.admx
    Office 2013: Outlk15.admx
  4. Copy the file appropriate to your version of Outlook to the C:\Windows\PolicyDefinitions\xx-xx
    Office 2016: Outlk16.adml
    Office 2013: Outlk15.adml
    where xx-xx is a Language Culture Name. For example, for English (US), the Language Culture Name is en-us. See: http://technet.microsoft.com/library/ee797784(v=CS.20).aspx
  5. Start the Group Policy Object Editor or the Group Policy Management Console.


The policy setting is applied on your client workstations when the Group Policy setting update is replicated. To test this change, at the command prompt, type the following command, and press ENTER:



After you run this command, start Registry Editor on the client workstation to make sure that the CacheOthersMail registry value exists on the client, and that it has a value of 0:



If you see this registry data in the registry, the Group Policy setting was already applied to this client.