John,
I know that someone is out there thinking it, so I'll just say it. Rollback to W7.
Are you using a Remote App, or a full RDC link?
Try manually connecting to that, or another RDC session, and see if it connects successfully.
Three thoughts:
<1> Try reinstalling the latest RDC to see if that solves the issue.
<2> Check the settings to see if the display settings in the connection are compatible
<3> Check your video driver - it could be that w10 can't run other display settings without a new driver.
