Does anyone have idea if one can walk-in to have finger print done for Naturalization despite the fact that the scheduled date is three weeks away.

Thanks

 Really? When I went to for my own fingerprints for GC, it didn't work. I got a snide remark from the security guard. I guess maybe exceptions are allowed based on one's situation.... 

Service center usually allow to have walk in finger prints if that center is not crowded on that day. You must have the finger print notice with you. They may/may_not ask you the reason behind early finger printing. If they ask you tell them the truth. They usually do not care as long as they are not busy and you are already scheduled for the printings in the future.  You may try your luck couple of times if you fail to have finger printed at the first time.

Thanks to all for your advice and comment.

I gave a shot this morning and it went fine. I had the finger printing done by walk-in 19 days ahead of scheduled date . Nobody asked me any question.

That's weird. Didn't they even ask you for the appointment letter?