I have just re-implemented VLANs into my network, I had originally removed these VLANs and had a flat network. I run an e-mail server behind the UTM and I use IMAP for retrieving e-mails both internally and externally. Since re-implementing the VLANs, I appear to have lost the remote IMAP connection. I have gone through the firewall and NAT rules which I have setup for IMAP, and I have updated the target's IP address to the new IP address of the e-mail server. Unfortunately, for some reason, port 993 (Secure IMAP), is not responding externally, where it had previously done so prior to re-instating the VLANs.
Here is the rule which I have, which did work previously.

I've tried using an online open port tester, Open Port Check Tool, but this reports that the the connection timed out.
This thread was automatically locked due to age.