Go to any ACS office with your doctor recommendation letter will let you do it.
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Application Sent:09/12/12 Vermont.Delivered:09/13/12. 797C Received:09/21/12 at 2:30pm. Biometrics Receipt: 9/24/12 3:00pm. Scheduled for: 10/5/12. Completed: 10/02/12. Application Aprroval:11/06/12. EAD Received: 11/9/12. SS Applied: 11/13/12. SS Received: 11/19/12. DL Received: 12/04/12.