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Could not open connection to the host, on port 23: connect failed.

I am using telnet from my client (192.168.70.21) to connect with my server (192.168.70.20).

I go this error message.  Can anyone tell me what might go wrong?
Capture4.JPG
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tommym121
Asked:
tommym121
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5 Solutions
 
tommym121Author Commented:
Sorry. I miss to send other images Inbound rule for Firewall on ServerCapture2.JPG
Capture3.JPG
Capture5.JPG
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exponeCommented:
This means that either your server (192.168.70.20) doesn't have a Telnet Server process running on port 23, so it is not accepting your telnet connection (from 192.168.70.21), or your firewall is not allowing traffic on port 23.

Try disabling your firewall temporarily and then test telnet. If it works, then you need to tweek the firewall. If it still doesn't work, then you need to check whether your server is running the telnet server.
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tommym121Author Commented:
The Telnet Server (Tlntsvr.exe) is running.

If I change the inbound connections: from Block (default) to Allow in the Domain Profile Tab of Windows Firewall with Advanced Security Properties,  Telnet works.

What I don't understand is that if my inbound rule for telnet is enable, why I nned to turn the inbound connections to be Allow
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exponeCommented:
You need to allow the inbound connections on port 23, so that Telnet Server (from outside your PC) can talk to the Telnet Client (which is inside your PC, hence the need for the inbound rule).
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tommym121Author Commented:
But if you look at the screen capture (capture1) -  Inbound rule for Firewall on Server.

Does it indicate the Telnet inbound Rule is enable with port 23 for the my server?
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exponeCommented:
Yes,  "capture1" above indicates that Telnet inbound Rule is enabled for port 23 on your server. This will allow the server to accept inbound telnet connections on port 23 from your PC.
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tommym121Author Commented:
But with that configuration, I still have the error.  That is why I am not sure what I miss?
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tommym121Author Commented:
And if you look at the  firewall logfile, it actually dropping the telnet packet even I enable Telnet.

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exponeCommented:
Different firewalls work different ways. The main thing is that you figured out how to make it work with turning the inbound connections to be Allowed.
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tommym121Author Commented:
I am using Firewall comes with Windows Server 2008 R2
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exponeCommented:
Good on you mate :-)
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tommym121Author Commented:
Thanks for your effort
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