The Department of Homeland Security requires many nonimmigrant visa seekers to pay a SEVIS fee prior to going to the U.S. Consulate or Embassy to apply for their visa. This applies to all new JMU students in F-1 or J-1 status unless you are transferring your I-20 or DS-2019 to JMU from another U.S. school.
The receipt, indicating you paid the SEVIS fee, is needed in order to process your request for a visa and must be obtained prior to attending your visa interview. It is strongly recommended that this fee be paid electronically by credit card, after which you will print out a receipt immediately. If you are unable to pay by credit card you may pay with a money order or cashier's check through a mail service, but you must allow additional time for processing of the receipt which you must have in order to apply for your visa.
For additional information about and/or to pay this fee, see the official SEVIS instructions.