Some days ago one of our users has opened a ticket that he is not able to change his Outlook language settings across the Outlook Web App (OWA).
After logging in to OWA he chose in the right corner the options to change his settings.
When he went to Options > General > Region and changed the language like is shown in the picture below:
He received the following error message:
“One or more folders have the same name as the following default Outlook folders: “Yammer Root”. Until you rename or delete all folders with conflicting names, you’ll encounter problems with your language settings in the Region and time zone settings in Options.”
However, that is not a cool deal and the user was unsure what to do now.
After a short investigation, I realised that I have to change the Mailbox Regional configuration on the Exchange server.
The easiest way to do that is using PowerShell.
In my case I run the following command:
Set-MailboxRegionalConfiguration –Identity alias -LocalizeDefaultFolderName:$true –Language en-us -DataFormat "dd/MM/yyyy"
After running this command for the User with the problem, the settings where complited without any future problems.