Good afternoon! I hope you're doing well.
We have two grades scales set up currently - the NTC Default which applies to Undergraduate and Postgraduate Taught degrees, and goes from 0 - 100 (with A - F marks for legacy!), and also an NTC PhD scale which is only for Postgraduate (Research) Degrees, and has only 'S' and 'U' grades, as this is all that is awarded at PhD level.
The error occurs where we have a student enrolled in a PhD level course, they cannot have grades from the other scale entered for them, even if they take classes from Undergraduate level. So, we might have a PhD student take an Undergraduate Greek class, say, to brush up on their language skills, but no grade can be entered for them. The error shown on the screenshot pops up, whether we try to enter the grade through the Academics > Classes side of things, or through the Student > Schedule and Registration > Update Class Details side with the grade override. So, it appears that the Grade Scale attaches to the student overall rather than the course or class.
Thanks for your help!