The university allows to you repeat a class, but only once ... you may not receive a grade in a class more than two times (unless the class is repeatable-for-credit). 'Grades' in this case include letter grades, and also W, WU, Incompletes and NC.
For the Academic Senate Course Repeat Policy, and the rationale behind it, you may visit http://www.sfsu.edu/~senate/documents/policies/F08-248.html
