I found this thread after Googling for the error message on flyemirates.com (in my case on the Advance Passenger Information page), "Please enter a valid contact number." In case it can help anyone else, the problem turned out to be that I was entering 1 for the country code (the A.P.I. page takes a contact number in 3 fields -- country code, area code, and phone number). The page's validation method apparently requires a 3 digit code. Entering 001 for the country code fixed the problem.