Urgent - Fingerprinting appointment question

[Jayraj]

My brother has filed for his N400 and recently he got the date for fingerprinting. The fingerprinting letter says that if you can't keep the appointment, send this original letter back with a request for rescheduling the date.

He is currnently out of country. My question is - can his friend mail this letter? There is no signature required.. one just has to check a place in the lower part of the letter.

[casper119]

Someone can send it for him, my sister in law sent it in for me after i missed my appointment, I was in Europe at the time.