I already tested this connection in Windows 10 64bit, and Windows Server 2012r2 64bit. I do the installation, it brings up the configuration screen in the google chrome browser and when I go through the configuration process of any backup situation in the 2nd tab where I put the cloud service that I am going to use which at home is mega and I ask to test the connection , I already get this message.
This is the first information screen.
This is the second screen that when clicking test connection already gives this error.
Still doesn’t show what’s going on underneath. Windows generally has fewer problems getting a TLS version that destination will accept. Windows 10 is also pretty new. I’d worry a bit more about Server.
If we think the problem might be in the compressed file list, you could test some other operations with Duplicati.CommandLine.BackendTool.exe, for example
get of a file. That could see if TLS is working.
You would need the destination URL from an Export As Command-line. Be careful what you do there. Alternatively edit the URL to an empty folder and let Duplicati.CommandLine.BackendTester.exe test.