Hi again. You had asked this in email as well, but I thought it might not be a bad idea to post it hear since you asked publicly as well.
I'm not sure why this would be. It's possible Windows 10 has new security measure in place to prevent this.
Since these are standard Windows error messages and we're using standard methods to connect, you should be able to bypass NEWT and track this down from Windows.
Try doing the same thing with a Windows command prompt by running it as elevated. Then use the "net use" command to connect to a remote PC, using the same credentials (or none) as you did with NEWT and the other app. This is basically the same method we and others use. Once you can replicate it from Windows, you can then possible get support directly from Microsoft, since it really is their error and their software.