On AIX, performing a "Check Password" on specific users fails with the below logs, Reset Password on the account work.
[MM/DD/YYYY HH:MM:SS] debug1: Sending command: sudo sed -n '/^managedaccount:/{n;p;}' /etc/security/passwd
[MM/DD/YYYY HH:MM:SS] debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
[MM/DD/YYYY HH:MM:SS] debug1: client_input_channel_req: channel 0 rtype eow@openssh.com reply 0
[MM/DD/YYYY HH:MM:SS] debug1: channel 0: forcing write
[MM/DD/YYYY HH:MM:SS] lastupdate = 1468419555
[MM/DD/YYYY HH:MM:SS] debug1: channel 0: free: client-session, nchannels 1
[MM/DD/YYYY HH:MM:SS] Transferred: sent 1456, received 2240 bytes, in 0.0 seconds
[MM/DD/YYYY HH:MM:SS] Bytes per second: sent 33315.7, received 51255.0
[MM/DD/YYYY HH:MM:SS] debug1: Exit status 0
[MM/DD/YYYY HH:MM:SS] Host unreachable or invalid account name
[MM/DD/YYYY HH:MM:SS] Unable to connect to AIX_6_1, or the account managedaccount does not exist or is disabled.
[MM/DD/YYYY HH:MM:SS] Processed the password check for managedaccount on AIX_6_1 in 3.4811991 seconds