The firewall is not connecting to any server via port 445.

Newbie504013 Lv1Posted Apr-01-2026 03:44

I have two 1100 firewalls, both located in different zones. I am attempting to connect via Telnet from the web console of one of the firewalls to a server on port 445, but I am unable to do so; I cannot connect to *any* server on port 445, although connections on other ports work fine. However, I *am* able to connect successfully on port 445 from the other firewall. What could be going on? It is not an issue with the Windows Firewall. Coincidentally, the firewall that is preventing the connection is the very one I have configured to function as a VPN server, and it is preventing my users from connecting to the shared folder server.

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Muhammad Abid Lv2Posted Apr-02-2026 12:33
  
The VPN firewall is blocking port 445 (SMB).

Reason:

After enabling VPN, the firewall treats traffic as untrusted
SMB (port 445) is often blocked by default due to security risks
It may be blocked by:
Firewall Policy
Application Control (SMB/CIFS)
IPS / Security Profile

Humayun Ahmed Lv3Posted Apr-01-2026 17:18
  
NGAF is blocking port 445 due to security or VPN access control policy.e Most likely caused by VPN resource restriction or IPS/App Control. Not a Windows issue.
Damai_Group Lv1Posted Apr-01-2026 10:01
  
Troubleshooting Guide: Unable to Connect to Port 445 via VPN Firewall

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1. Verify Application Control Policies

- Navigate to Policies > Access Control > Application Control.
- Look for policies that apply to VPN traffic (source = SSL VPN interface or VPN zone, destination = internal network zone).
- If no policy explicitly allows TCP 445 (SMB), create a new Allow rule for that port.
- Ensure the rule is placed above any Deny rules that might block the traffic.

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2. Use Precise Traffic Analysis to Identify the Block

- Go to System > Troubleshooting > Precise Traffic Analysis.
- Enter the source IP (VPN client virtual IP) and destination IP (file server IP). Set protocol to TCP and port to 445.
- Start the analysis and attempt the connection from a VPN client.
- Review the Data Flow Diagram. It will show exactly which module (e.g., Access Control) blocked the packet and may provide a direct link to the policy.

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3. Check for Virtual IP Pool Conflicts

- Navigate to Network > SSL VPN > Virtual IP Pool.
- Verify that your file server’s IP address is not within the IP range listed.
- If an overlap exists, change the Virtual IP Pool to a different subnet that does not conflict with internal servers.

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4. Inspect Firewall Rules for Inter-Zone Traffic

- Go to Policies > Access Control > Firewall Rules.
- Confirm there is a rule allowing traffic from the VPN zone to the internal server zone on TCP 445.
- If such a rule is missing or placed too low in the order, add it or adjust the rule order accordingly.

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5. Test with a Temporary Permit-All Rule

- Temporarily create a broad Allow rule at the top of your Application Control or Firewall policy list for traffic from the VPN zone to the file server on any port.
- Attempt the connection again. If it succeeds, the issue is confirmed to be policy-related, and you can refine the rule to be more specific (only port 445) rather than leaving it wide open.

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6. Verify VPN Client Network Access Settings

- Go to Network > SSL VPN > Resource Access.
- Ensure the file server’s IP and port 445 are included in the resources assigned to the VPN users or user group.
- If missing, add the appropriate resource and re-assign it to the affected users.

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7. Review System Logs for Additional Clues

- Navigate to System > Logs > Access Control Logs.
- Filter by source IP (VPN client), destination IP (file server), and port 445.
- Look for entries showing Deny or Drop to confirm the block and identify which policy caused it.

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By working through these steps in order, you should be able to isolate the cause and restore connectivity to port 445 through the VPN firewall.

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