EFibre Problem

Hi,

I was hoping someone might be able to help with an issue that has occurred since upgrading to eFibre.

We have the F1000 modem, connected to a ZyXel firewall. Behind the firewall, we have a number of computers, as well as a server.

Before upgrading to eFibre, we had the D1000 modem. Everything was working as intended when the D1000 was in use.

Now, we can not access certain apps on mobile devices (e.g. weather apps) when connected to the network. We also can not retrieve/send emails from mobile devices while connected to the network. When we're off the network (e.g. connecting from elsewhere), no devices can send/receive emails from the exchange server at the office.
We've set the F1000 up identically to the D1000 that was in place before. The F1000 has the hardware firewall added to the DMZ, which should allow all traffic to pass through to the firewall unfiltered. It appears, however, that port 443 is being restricted by the F1000.

Has anyone else encountered such an issue, and do they have a possible solution?