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I have successfully hosted NWN1 dedicated servers in the past but, with my new router and computer, nobody can connect.

So far I have:
1. Set my computer's local IP to a static address
2. Forwarded ports 5120-5300, 6500, 27900, and 28900 on my router to my computer's static local IP address using UDP
3. Opened UDP ports 5120-5300, 6500, 27900, and 28900 in my Windows firewall for all applications and all networks (private, public, and domain)
4. Disabled my router firewall entirely
5. Checked the "post to internet" box in the nwserver.exe interface
6. Attempted to direct connect to the dedicated server using my external IP address and port 5123

Despite this, the connection just times out. What else can I try? I have no issues connecting to persistent worlds and can even connect to the dedicated server that I set up on my brother's computer last year.

I am running Windows 10. Unfortunately, I am not able to completely disable my Windows Firewall because this is a school-issued laptop and the administrators have locked that. However, as I stated above, I have allowed all incoming traffic from ports 5120-5300, 6500, 27900, and 28900 through my Windows Firewall.