change folder language (registry)

For example, you might want to reset folder names for all users when you deploy Outlook to synchronize users' folder names to the User Interface Language of their version of Outlook. This could be useful, for example, if a corporate-wide process has initialized new mailboxes before new users have started Outlook for the first time. In this case, the mailboxes will end up with default folders in the language of the server. (Note that users can, instead, specify the /resetfoldernames option on the Outlook.exe command line to synchronize the folder names on their computers.)

To reset folder names when deploying Outlook

In the Custom Installation Wizard, go to the Add/Remove Registry Entries page.
Click Add to add a registry entry for ResetFolderNames.
On the Add/Modify Registry Entry page, select or type the following:
Under Root:, select HKEY_CURRENT_USER.
Under Data type:, select Dword.
In the Key: field, type Software/Microsoft/Office/11.0/Outlook/Setup.
In the Value name: field, type ResetFolderNames.
In the Value data: field, type 1.
Any non-zero value will cause Outlook to synchronize the user's folder names to the User Interface Language of Outlook.