< #5.5.0 Smtp;554 Sorry, Message Looks Like Spam To Me> Grade Conversion Based Out Of A 5.0 Scale To A 4.0 Scale?

Grade Conversion based out of a 5.0 scale to a 4.0 scale? - < #5.5.0 smtp;554 sorry, message looks like spam to me>

Just now I am still studying abroad in Singapore and at the National University of Singapore. I have my notes back and one of my notes I have a D +. This is regarded as D + 1.5/5.0 points. However, Singapore is not only C-you go from D to C. I try to figure out, how this letter if they would be into a 4.0 scale. Can anyone help? = (