Answer

To add a hosts entry that resolves local.example.gen to 192.168.128.10 on Windows 10, Windows 11 or Windows Server 2025, follow these steps:

1. Open Notepad as Administrator

• Search for Notepad in the Start menu.
• Right‑click and choose Run as administrator. This is required because the hosts file is protected by system permissions.

1. Open the hosts file

• In Notepad, click File → Open.
• Navigate to C:\Windows\System32\drivers\etc\.
• Change the file‑type dropdown from Text Documents (.txt) to All Files (.*) so you can see hosts.
• Select hosts and click Open.

1. Add the entry

     192.168.128.10    local.example.gen

• Scroll to the bottom of the file (or to an empty line) and add the following line exactly as shown:
• Ensure there is at least one space (or tab) between the IP address and the hostname.

1. Save the file

• Click File → Save (or press Ctrl + S).
• If you receive a permission error, confirm the UAC prompt and save again.

1. Flush the DNS cache (to apply the change immediately)

     ipconfig /flushdns

• Open Command Prompt as administrator (right‑click Start → Windows Terminal (Admin) or Command Prompt (Admin)).
• Run:

1. Verify the resolution

     ping local.example.gen

• Open a new Command Prompt (no admin rights needed).
• Ping the hostname:
• You should see replies from 192.168.128.10.
• Alternatively, use nslookup local.example.gen to confirm the IP returned.

1. Troubleshooting tips

• No effect after editing – double‑check that Notepad was run as administrator and that the file was saved correctly.
• Incorrect IP returned – ensure there are no stray characters, extra spaces, or duplicate entries for the same hostname.
• Ping fails – verify that the target device (192.168.128.10) is reachable on the network and that no firewall is blocking ICMP.

What to check next

• Confirm that the hostname local.example.gen is not already defined elsewhere (e.g., in DNS or another hosts entry).
• Ensure the IP address 192.168.128.10 is assigned to the correct network interface on the target machine.

Following these steps will add a permanent local DNS entry for local.example.gen on any Windows 10/11/Server 2025 system.