Using PuTTY and hitting a scary error that says “Fatal Error: Network Error”? Don’t panic. You’re not alone, and the fix is usually easier than you think. Whether you’re a seasoned sysadmin or a curious beginner, this guide breaks things down in a fun and simple way.
TL;DR
PuTTY’s “Network Error” usually means it can’t connect to the server. This could be a firewall problem, wrong IP address, or the server is simply down. Try checking your internet, restarting the router, or making sure the right port is open. If all fails, call your server admin buddy!
What is the PuTTY Fatal Error?
This error usually pops up when PuTTY, the remote terminal program, fails to connect to your server over the network. The full message might say:
“Network error: Connection refused” or “Network error: Connection timed out”
Translation? Either the server is ghosting you, or there’s a techie roadblock in the middle.
Why Does This Happen?
There are several goblins in the tunnel between you and your server. Some of the common causes include:
- Wrong IP address or hostname – Yup, even one wrong number messes it all up.
- SSH is disabled – If the server isn’t listening for you, no handshake happens.
- Firewall says NOPE – A firewall on your machine or the server can block the connection.
- Network issues – Sometimes it’s just your Wi-Fi being dramatic.
- Wrong port – SSH usually uses port 22, but some servers use different ones.
So how do you fix this? Let’s dive in.
Fix 1: Check the IP Address and Port
This might sound basic, but double-check the IP address or hostname. Make sure you entered it correctly into PuTTY.
Also, confirm the port number. If the server uses a different port (not 22), you need to enter that manually in PuTTY’s settings.
Fix 2: Ping the Server
Try pinging the server to see if it’s even alive. Open a command prompt and type:
ping yourserver.com
If you get a reply, it means the server is reachable. If not, your network might be the problem.
Fix 3: Test the Port with Telnet
To see if the SSH port is open, try using Telnet:
telnet yourserver.com 22
If the screen goes blank or says “Connected”, the port is working. If it says “Connection refused”, then SSH might be turned off or blocked on the server side.
Fix 4: Restart Your Router or Modem
Sometimes, your internet connection needs a quick nap and a fresh start. Power cycle your router and modem. Unplug them, count to 10 (slowly, with feeling), and plug them back in.
Fix 5: Whitelist PuTTY in Antivirus or Firewall
Your PC’s firewall or antivirus may think PuTTY is suspicious. You rebel hacker, you.
Add an exception in your firewall/antivirus settings to allow PuTTY to connect freely.
This can usually be done via:
- Windows Security → Firewall & Network Protection
- Select “Allow an app through firewall” → Add PuTTY.exe
Fix 6: Check If SSH is Enabled on the Server
If you’re managing the server (or know someone who is), make sure SSH is running. Use the following command on the server:
sudo systemctl status ssh
If it’s not running, start it with:
sudo systemctl start ssh
Fix 7: Use Correct Protocol
PuTTY can connect using different protocols like SSH, Telnet, or Rlogin. Make sure you are using SSH unless your server requires something different. You can select the correct protocol on the PuTTY home screen.
If you’re trying to SSH and picked Telnet in PuTTY, your connection will either fail or talk gibberish.
Fix 8: Server is Down or Rebooting
It could just be that the server is offline.
Pro tip: Servers like to reboot quietly and come back grumpy. Give it a few minutes, then retry the connection.
You can also try connecting via a different device to see if the issue is on your end or the server’s side.
Fix 9: Flush DNS Cache
If you’ve recently changed DNS settings or the server’s IP has changed, your computer might be remembering the old info.
To clear the DNS cache on Windows:
ipconfig /flushdns
Now, restart PuTTY and try again. Go on, be brave.
Fix 10: Use a Different Network
Some networks (like public Wi-Fi or office networks) block SSH traffic. Try switching to a mobile hotspot or different Wi-Fi to test.
Fix 11: Update PuTTY
Using an old version of PuTTY? Get the latest one from the official PuTTY website.
Newer versions fix bugs and handle newer encryption methods better. Always nice to be up-to-date.
Bonus Fix: Enable Logging
If all else fails, enable session logging in PuTTY.
- Go to “Session”
- Expand “Logging”
- Choose “All session output” and pick a file
Then try connecting and check the log. Something in there might reveal what’s going wrong.
When to Call for Extra Help
Still no luck after trying all this? It might be time to call your server admin, network team, or tech-savvy friend. Tell them:
- The exact error message you received
- What fixes you already tried
- Whether the server is reachable at all by ping or telnet
This will help speed things up and make you look smart (bonus!).
Wrapping It Up
The PuTTY “Network Error” may seem frustrating, but it’s almost always a sign of something small. Whether it’s a typo in the IP, a firewall block, or an SSH service playing hooky, most causes are fixable without throwing your laptop.
Try each solution one at a time. Slow and steady wins the server race.
And remember: half the battle is just staying calm and caffeinated.
