Just an FYI I came across this when I was approving updates. In case you run into the issue that Outlook is displaying different languages in the UI check to see if this (these) updates are installed. I have seen similar updates for other versions of office as well. (I do not approve them though).
After you install this security update, Outlook may display mixed languages in the user interface. To fix this issue, follow these steps:
1. Uninstall security update 4011086. Read the following section for information about how to do this.
2. Install Security Update for Microsoft Office Outlook 2007 (KB4011110).
From
https://support.microsoft.com/en-us/help/4011086/descriptionofthesecurityupdateforoutlook2007september12-2017