You have two differnt file types from the two posts you have made, the 14th of june has a .cap file and the latest has a .ivs file.
using --ivs will only write initialisation vectors and connot be used for WPA handshake cracking! You will not capture a handshake with this option.
so run airodump-ng, in monitor mode, on the correct channel, with a .cap save file, when a WPA client connects to the network.
simply connect a wireless client to your access point while the above is running and you will get a handshake to use with aircrack.
if you need to you can DeAuth a connected client with Aireplay-ng to get it to re-connect and capture the handshake then.
you must use the .cap file which captures the handshake and the passphrase must be in the dictionary you use or it wont work.




