Read the complete incomplete grade policy here.
An “incomplete” or “I” grade is awarded when a student’s work is satisfactory and the student is passing the class but a minor (yet essential) requirement for the class has not yet been completed for reasons that are acceptable to the instructor. Effective Winter 2005, students have one calendar year to complete the work and have the “I” changed to a regular grade. If the grade is not changed by the instructor, the “I” will be converted into an “F” and the “F” will be factored into the student’s GPA.
“I” grades can only be changed by the instructor of the course. Students who register and complete the same class in another term will earn a grade for that term. The original “I” will remain an “I” in the original term until the 12-month period is over. Then, it will convert to an “F.”
See if this fictional scenario helps you understand it better: If you took J1005 from Prof. Jack Christensen in Fall 2008 and earned an "I," you need to work with Prof. Christensen within one calendar year to have that incomplete removed. If you don't, after Fall 2009, that "I" grade will automatically change into an "F." Not good for your GPA.
After receiving the "I," you may decide to register for J1005 again for Winter 2009 and take it with Prof. Tina Haas instead. This is a common mistake. If you do this, you will receive a grade for J1005 for Winter 2009. Your "I" grade from Fall 2008 will not go away and will become an "F" after one year. You cannot do this even if Prof. Christensen was teaching J1005 again in Winter 2009.