Hi @Jack Chuong ,
According to my research:
1.Please try to re-create a outlook profile for the user's mailbox in question.
2.Regarding the parameters you mentioned:
- About the “GlobalWebDistributionEnabled” parameter is $false by default. But in Exchange 2013 CU7 or later, Microsoft recommend that you use the value $true for this parameter. The Client Access services on any Mailbox server can proxy incoming OAB download requests to the correct location.
2) About the “VirtualDirectories” parameter, In Exchange 2013 CU7 or later, Microsoft recommend that you set this parameter to $null, and then set the GlobalWebDistributionEnabled parameter to $true. Please noted that to use this parameter, the value of the “GlobalWebDistributionEnabled” parameter must be &false.
3) After changing the parameters, please run the iisreset in the Run start as Administraotr to restart the IIS.
4) To prevent wrong changes, please back up your current settings before making changes.
For more information about these parameters, you could refer to: Set-OfflineAddressBook
3.Please run the following command to generation of OAB, then check whether the OAB generation is normal under the path %ExchangeInstallPath%\ClientAccess\OAB\<ObjectGuid> file.
Get-OfflineAddressBook | Update-OfflineAddressBook
In addition, after the OAB download fails, are there any related error logs in event viewer? If so, please share with us, but please pay attention covring your personal information.
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