Have you done a full factory reset on te new hub? and have you matched EVERY setting from the old one?
Is te hub you have purchased of te same build standard - both hardware and software as the old one? If not you may need to get a firmware update.
After the reset, the software updated to the version I had previously after a couple of days.
The build and firmware are identical.
The only difference is that I have migrated from AVG to MacAfee but while it didn't work with the MacAfee firewall disabled, the ports I require are checked in the MacAfee firewall as being permitted.
Even if 4125 was blocked, 80 and 443 would allow me to access the web site and they both show as 'open' on a variety of software scanners.
Also try disabling the Windows firewall. Sometimes those windows automatic updates can cause this.