Windows 10 Pro, RDP Server, "An internal error has occurred"

I've expirenced this issues several times lately, and one workaround is to connect to the machine locally if possible (or via a VmWare console).

Otherwise you can restart the Remote Desktop Services in services.msc (and say yes to also restart the dependant service).

But a permanent solution would be preferable.

Deleting saved credentials in the client.rdp session and re-entering solved the problem for me. Edit Delete

Any Windows 10 update can break anything in the system, including making it unbootable.

You will have to know when the RDP stopped working, check what update applied at that point and remove that update. TCP 64 error was found to appear after updates in several cases. So make sure you find the update that did it and also try to install update KB3200970 if you don't have it already.

Restarting the Remote Desktop Service worked for me. You don't have to conect locally to do that. In your local computer run services.msc then go to Action, connect to another computer, and choose the remote computer. Once connected find the service and restart it.

I had this happen today. I noticed in the Security event log, numerous events each time i tried to connect:

Credential Manager credentials were read.

Subject:
    Security ID:        SCREWDRIVER\Ian
    Account Name:       Ian
    Account Domain:     SCREWDRIVER
    Logon ID:       0x63814
    Read Operation:     Read Credential

This event occurs when a user performs a read operation on stored credentials in Credential Manager.

Which told me it was trying cached credentials over and over. I went back into Remote Desktop Connection client and deleted the cached credentials:

And then re-connected, re-entered the password, and it worked.

Warning Event 226, RemoteDesktopServices-RdpCoreTS
    General: RDP_TCP: An error was encountered when transitioning from StateUnknown in response to Event_Disconnect (error code 0x80070040)

Warning Event 142, RemoteDesktopServices-RdpCoreT
    General: TCP socket READ operation failed, error 64

You also get those messages in the RemoteDesktopServices-RdpCoreT log if there are issues with your smartcard certificate. In our case the certificate was revoked however we saw no indication of it when using Remote Desktop Connection from a Windows 10 client.

The same error occurs with Windows Server 2019.

In addition to the Eventlog entries above I see Error Event 1006 Microsoft-Windows-TerminalServices-RemoteConnectionManager/Admin The RD Session Host server received large number of incomplete connections. The system may be under attack.

Using Wireshark I only see one connection attempt. The Server sends TCP RST what obviously causes the eventlog entries we see. Maybe the defaults from older versions of Windows got discarded. I have set MaxOutstandingConnections to 3000 as @Dexmox reposted here and can confirm it works on both Server and Client Versions of Windows.

$registryPath = "HKLM:\SYSTEM\CurrentControlSet\Control\Terminal Server"
$Name = "MaxOutstandingConnections"
$value = 3000

IF(!(Test-Path $registryPath))
  {
    New-Item -Path $registryPath -Force | Out-Null
    New-ItemProperty -Path $registryPath -Name $name -Value $value -PropertyType DWORD -Force | Out-Null}
 ELSE {
    New-ItemProperty -Path $registryPath -Name $name -Value $value -PropertyType DWORD -Force | Out-Null}

I have encountered similar errors with RDP and found that disabling local resource sharing resolved the issues for me.

Under advanced tab of the RDP connection find "if server authentication fails". The default is set to Warn me. Change it to "connect and don't warn me". This just worked for me on multiple machines.

Try deleting saved credentials from RDP session. Then re-enter and save. Use RDP template below. This worked for me on three machines where I kept getting the "internal fault" error while connecting.

update try this example. Change full address X.X.X.X and USERNAME then save as

xxxx.rdp

screen mode id:i:2
use multimon:i:0
desktopwidth:i:3840
desktopheight:i:2160
session bpp:i:24
winposstr:s:0,3,0,0,800,600
compression:i:1
keyboardhook:i:2
audiocapturemode:i:0
videoplaybackmode:i:1
connection type:i:7
networkautodetect:i:1
bandwidthautodetect:i:1
displayconnectionbar:i:1
enableworkspacereconnect:i:0
disable wallpaper:i:0
allow font smoothing:i:0
allow desktop composition:i:0
disable full window drag:i:1
disable menu anims:i:1
disable themes:i:0
disable cursor setting:i:0
bitmapcachepersistenable:i:0
full address:s:X.X.X.X
audiomode:i:0
redirectprinters:i:0
redirectcomports:i:0
redirectsmartcards:i:1
redirectclipboard:i:1
redirectposdevices:i:0
drivestoredirect:s:
autoreconnection enabled:i:1
authentication level:i:2
prompt for credentials:i:0
negotiate security layer:i:1
remoteapplicationmode:i:0
alternate shell:s:
shell working directory:s:
gatewayhostname:s:
gatewayusagemethod:i:4
gatewaycredentialssource:i:4
gatewayprofileusagemethod:i:0
promptcredentialonce:i:0
use redirection server name:i:0
rdgiskdcproxy:i:0
kdcproxyname:s:
username:s:USERNAME
gatewaybrokeringtype:i:0

As of some Windows update within the past 9 months, this problem no longer occurs. So I assume that Microsoft finally got it sorted out.

Logging another possibility for folks to try - this just fixed connecting from my Windows 10 dev box to a 2008R2 server:

If your RDP client box has unusual crypto settings, you may get "An unexpected error has occured" when trying to connect to a perfectly normal RDP server.

I was checking that various clients could still connect to an app on my dev box with restrictive protocols, so I used Nartac's IISCrypto to set my dev box to Best Practices and rebooted. At that point, I could still connect.

Then I restricted things further, aiming for an A+ from SSL Test. Knocked out a few combinations, got my A+... and found later that I couldn't connect to anything over RDP!

So, if you've been hardening your IIS crypto beyond Best Practices and find you can't connect out from the hardened machine over RDP, try setting things back down to Best Practices.

As Wilson Waters noted, you may be being flooded by hacking attempts. Do your firewall rules allow inbound RDP connections from anywhere? You should restrict the scope to your own IP address(es).

For example, for Windows Firewall on the server:

1. Open Windows Firewall with Advanced Security.
2. Click Inbound Rules.
3. For each inbound rule whose name starts with Remote Desktop:
   1. Double-click the rule.
   2. Go to the Scope tab.
   3. Under Remote IP addresses, check These IP addresses.
   4. Add the IP addresses to restrict inbound RDP connections to.

for me the issue seemed to be that i was sharing the rdp via MS cloud and saving credentials. I was not able to delete stored credentials as the ui was not showing the option so what i opened the .rdp file in VS code and made the following changes

1. update prompt for credentials:i:0 -> prompt for credentials:i:1
2. remove this line gatewaycredentialssource:i:
3. update promptcredentialonce:i:0 -> promptcredentialonce:i:1

then save as to a local dir that is not stored in MS cloud so it would no happen again

For me, it was because I was in the middle of a hacking attempt. I kept trying to RDP to my VPS server, and got the error mentioned here 9 out of 10 times. When I did manage to log in, there were about 5 "Audit Failure" messages in the Security Event Log every second. It looked like someone was trying to brute force the administrator password. The RDP error occurred because the maximum number of simultaneous connections had been reached because of this.

I wasn't able to limit my firewall to only my IP address as mentioned in another answer, so instead I changed the port that RDP listens on, and opened up that port in the Windows Firewall, and the attacks (and the error) went away - at least for now. I used this method described on the Microsoft website: https://docs.microsoft.com/en-us/windows-server/remote/remote-desktop-services/clients/change-listening-port

I just try the following and worked:

Just try to connect with a bib existing username and password, then mstsc will try to connect, in fact it will connect, and then the windows server screen will tell you that username and password entered are bad, then simply user correct name and pass and will work.