Can no longer access one of the domain hosts via VPN

SYSADMIN

We have a TZ400 with SSL VPN. Remote users access workstations in the office domain via NetExtender. This has been working fine for a while, but recently I cannot access one of the Windows 11 workstations using Remote Desktop via NexExtender/VPN. If physically in the office, Anyone can use Remote Desktop to access this workstations. It just doesn't work remotely (outside the office). All other configured workstations can be accessed from the outside — just this one is a problem.

All workstations are members of an Active Directory domain and remote access and firewall are controlled by the domain controller. Remote Access settings show remote access for this computer to be ON.

Any idea what I could look at to figure out this problem?

SYSADMIN

I've investigated everything I can think of with respect to firewalls including getting Norton technical support involved. Nothing appears off there, nor different from every other workstations. At this point I'll open a ticket with SonicWall.

Ajishlal

@SYSADMIN

check Windows Firewall or endpoint Firewall restrictions from remote IP.

SYSADMIN

Thanks for you response. The problem I see with that idea is that the TZ400 is the LAN IP 192.168.0.1, so I don't think the workstation is seeing it as anything other than a local host. I've checked the event viewer for any event 4825 (remote access denied) and there are no such event. One thing that might be the problem: The firewalls on other workstations on the domain say, "For your security, some settings are managed by your system administrator", whereas on the "problem" workstations it says, "These settings are being managed by vendor application Norton 360."

I'll try changing that to the "… managed by system administrator" and see if that helps.