Hi,
- Did you make any changes before the issue occur?
- Have you tried with another account? Was the issue persisting?
- Kindly correct me if my understanding was wrong. The issue behavior was that after you have changed the second language(from language box on task bar), but every time when you clicked the mouse and tried to type in the second language, it showed up the main language.
Could you please confirm when it prompted the Greek keyboard to type, was the language box showing as the same choice? - You could check the value under following path, which defines the keyboard layout
HKEY_CURRENT_USER\Keyboard Layout\Preload
https://social.technet.microsoft.com/wiki/contents/articles/6281.how-to-set-the-keyboard-layout-through-group-policy-gpo.aspx
Thanks,
Jenny