It does not affect the process in any way that the client is using Vista. The most common reason to why people are unable to capture the handshake is that they do not realize that they need to be close enough to both the AP and the client in order to capture the full 4-way handshake. I would suggest that you use wireshark to open your cap file and check whether or not you are intercepting even a part of the handshake, most likely the AP side. If this is the case, then you will need to move closer to the client in order to get the full handshake.


