I got this error while trying to connect to my Citrix gateway after an Azure AD authentication. The Netscaler were just provisioned on a SDX. The SDX was time sunchronize with my NTP server but something seems odd with this message :
Invalid time in the Message sent by the Peer. Please ensure time synchronization between Netscaler and the Peer
Checking the date on the first Netscaler gave me a totally wrong time.
Getting the current date and time :
and then to force a time synchronisation :
Everything should be back to normal and connexion is ok.