Magnet street names need a Suffix
CASS Certification forbids coding a Magnet street name unless the street ends with a suffix.For example, if you have an address of 100 Avenue, that address will not be able to validate until you add its correct suffix (st, blvd, ave...whatever it is) because Avenue, though it's a street name in the case of the example, is also the name of a suffix.
So if you have an address that won't validate, check the street name. If the street name is the same word as a word that is considered a suffix, then the address needs a suffix added to it in order to validate.