We've had a power cut earlier which messed up our SonicWall (TZ 190, SonicOS Enhanced 18.104.22.168-4e). Half of our NAT rules went missing, firewall rules had wrong IP addresses etc. - no idea what happened there.
I've changed all the rules and everything is working again - apart from OWA and Active Sync.
I'm confident that NAT is working fine - there's a couple of other firewall rules using the same address objects etc. which are working fine. (Mimecast access for LDAP synchronisation and SMTP acccess for example).
The firewall rule configured allows POP 3, HTTP and HTTPS.
POP 3 access is working, HTTPS access isn't. I have changed the IIS config for OWA temporarily to not require SSL and I can access it fine through HTTP. When SSL is enabled I also receive the message to say that I need to access it via https.
However, when accessing it via https all I get is "Page cannot be displayed". Everything is fine internally - just not working externally. Nothing in the logs. Accessing it via the IP address doesn't work either so I'm pretty certain there's a problem with the SonicWall.
I've created a new rule allowing HTTPS from any source to any source to test and this isn't working either.
Does anyone have any ideas? I'm absolutely lost.