That your router has its firewall on. I will be short about this that routers always had a natural firewall due to NAT so the new firewall they added tends to break stuff like this with little added security. Try it with the router firewall off.
Sorry, I'm not Seagate support but have fixed a few.
I just bought a Seagage 4TB Personal Cloud yesterday and it works fine when I access it through my home WiFi network. However, I can't see any of the files when I'm at work - the folders are blank. So I rebooted and when I try to sign in through Seagate Access, I get the following message: "Failed to connect to the seagate sdrive server". I am entering my username and password correctly. Anybody any ideas?

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