we've installed IPS 4240 since 6 months ago and everything worked fine. Then I noticed time in IPS was not correct, then in the IDM, I've changed summer time to 60 minutes offset to get the right time from NTP. then reboot the IPS, since that time users inside the network are not able to connect to internet, and basically traffic from inside to outside is blocked. But traffic from outside to inside is fine and outside users are able to hit to the web server in DMZ zone.
any idea would be very appreciated.