To me it looks like you simply do not have network connectivity to the SFTP server. Unless you prove otherwise, I do not think you have a problem with WinSCP. So imo it makes no sense to try to solve it be reinstalling WinSCP. Rather check for your network/firewall.

Yes, I normally use SFTP, other connection within the WinSCP fail. I have not tried to SSH or telnet. Again just starting seeing this issue last week. WinSCP is only installed on the Windows 2016 server. WinSCP is not installed on any other device. System is airgap and there is no external communicates but via external media.

Ping and directly login works fine.

Is this SFTP? Can you login with any other SFTP/SSH client?

I run in to above subject line error this week. First time I seen this while using the WinSCP software which is used for file transfers. Between Windows 2016 Server to RHEL Server 7.9. Below is the information that I have available.

1. I am able to ping from one server to the other.
   
2. I am able to login to the Linux system while using my Domain login.
   
3. WinSCP has been work fine with no issue to report up until this week.
   
4. WinSCP version is 5.15.x
   
5. Fully error Message "Network error: Connection to <IP Address> refused" then provides option to retry 3 seconds)
   
6. I try to reboot both systems – results no change
   
7. My login has been the only logon used for both servers.
   

Please provided any assistances to help my correct the software. As a possible troubleshooting step I am considering is to uninstall and reinstall the software. This step will not happen until early next week.

Thanks,
Robert