Hi Kate,
Hope you are fine.
I just republished the localizations for the customers version (client, server and localizations).
Please ask the customer to download a new client from MyStandard.
If this does not solve the issue, ask the customer to add Norwegian on the language field in the person record
(SY>>Settings>>Persons>>Open the specific persons - person record>>navigate to the Language field and use paste special and select NOR. If not possible to select NOR, just type NOR and save>>restart the client).
Let me know how it goes.
Regards,
Martin