QUOTE(indianheart @ Feb 27 2008, 12:30 AM)

I beleive it is always the uscis number for calling NVC. I dont think there is an option because of all the different embassy's around the world there would not be enough time to list those 3 letters (I have just always used the uscis number to get to the automated system...the NVC case number to talk to an operator)
recipy for calling NVC WITH EMBASSY NUMBERS

603 334 0700, 1,1,2, the embassy leters, 1, case number after 3 letters #, 1
voila

I always call like that.