Hi, I finally fixed it. It turns out some of the firewall rules didnt get loaded properly when I imported the config.xml. You could see the rules in the GUI and they looked totally normal but some rules weren't functioning properly or only partially. On my guests vlan one computer that had a reserved IP via DHCP worked fine while other normal DHCP users on the same VLAN could ping external IP's but not operate on something like port 443. All I had to do was to duplicate the "Allow internet" rules and put them up higher than the old rules then everything returned to normal. It's a bit odd that rules go wrong when importing. I tried the wipe/rebuild/import-config twice and it did the same thing twice. I even exported the config twice. Which VLANs it effected did change between attempts but it was the same rules. Like you I would of thought it was something to do with the interface assignments.
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