Slow Initial RDP Connection to Windows 10

Since upgrading a machine from Windows 8.1 Professional to Windows 10 Professional (workgroup, no domain membership), I've been experiencing a rather strange issue that I can't figure out. The initial remote desktop connection is very slow to connect (on the order of two minutes). However, after the initial connection is made, I can close the connection and reconnect almost immediately. Also, after the initial connection is made, I can close the connection and reconnect using another machine entirely without experiencing the long delay. I've tested the remote desktop clients on Windows 7, 8.1, and 10, and all experience the same slow initial connection to the Windows 10 machine, so I believe the problem lies on the server side.

Things I've tried so far:

• Turning off "Automatic Root Certificates Update" via local computer policy:
  (Computer Configuration -> Administrative Templates -> System -> Internet Communication Settings -> Turn Off Automatic Root Certificates Update).
  Suggestion from technet, by user "dsoic" midway down the page. It was also suggested to disable CredSSP, but I don't think disabling Network Level Authentication is a good choice.
• Forcing TCP as the only RDP transport protocol
  (Computer Configuration -> Administrative Templates -> Windows Components -> Remote Desktop Services -> Remote Desktop Session Host -> Connections -> Select RDP transport protocols),
  suggested by user "Jayson Allen" on spiceworks. I also checked the FIPS setting, but on Windows 10 it appears to be disabled by default.

Neither has improved the situation. Does anyone have any advice on how to proceed?

EDIT: The Threshold 2 update has corrected this issue on my system.

It's a result of aggressive auto-tuning of the connection which causes the delay on startup. Running the following should resolve your issue.

netsh interface tcp set global autotuninglevel=highlyrestricted

More details: Remote Desktop slow problem solved

Well, after being unable to determine the root cause of the issue, I tried a fresh install of Windows 10 Professional. The reinstall has corrected the slow initial connection issue, so all that I can say is that this problem was most likely some sort of corruption or setting issue caused by the upgrade process.

Edit: I spoke too soon. The issue started again approximately one week after reinstalling Windows. I'm still searching for the root cause.

I have solved this problem by changing the Mircosoft account to local account .

Edit: RDP initial connection is sometimes still slow , but better than using remote Microsoft account .