.. or RDCMan (Remote Desktop Connection Manager) crashes to a Windows Error.

So, I have two annoying issues. They have been with me for over 12 months and no amount of Googling or talking to others about it seemed to fix anything. I gave up.

Recently, I got fed up with it again and had a fresh look and a fresh Google. Finally, fixed.

For others this might be old news, but as it took me ages to find this, I thought I would document it.

Symptom one

Open Mstsc, put in the server name, go to the Options, Advanced and setup Connect from anywhere. Setup an RD Gateway server. Return to the main logon and connect.

It pops up for credentials to access the RD gateway. You put them in, click continue. It goes away and thinks. Comes back and pops up the window for the credentials to access the RD gateway. The username and password boxes are blank again. Again, fill them in, connect. It goes away and thinks. Comes back and pops up the window for the credentials to access the RD gateway. I am in a loop. Leave the boxes empty, connect, It goes away and thinks. Comes back and pops up the window for the credentials to access the RD gateway. Press Cancel, It goes away and thinks. Comes back and pops up the window for the credentials to access the RD gateway.

I can’t get out of this without using Task manager and killing mstsc.exe

Symptom two

In conjunction with this, when I RDP direct to a machine, it pops up the certificate warning message, click ok, “Windows has caused an error” and Mstsc.exe exits. No amount of trying, gets me in.

Symptom three

When I use Remote Desktops Connection Manager (RDCMAN) and I add a new server, tell it the RD gateway settings, then try and connect, it crashes.

 

Direct RDP via Rdcman seems to work fine.

Environment

  • Windows 10 Home
  • Latest RDP version from Windows Updates
  • Latest Rdcman I could find
  • Connecting to Windows 7, Windows 10, server 2008, 2008R2, 2012, 2016 and 2019 via RD Gateways

What was the cause?

Incorrect use of NTLM by my Windows 10 Home PC.

There are two ways to address this.

Windows 10 Home

Firstly, I have Windows Home. I lack the local Security MMC console so, I had to make my changes by the Registry.

All changes in the registry carry risks. Please be sure to backup your registry. Please only change what I mention here. If you are at all doubtful, back away from the keyboard !

Go to start > run (Right click the Windows icon on the left hand side, select Run)

Type: “regedit” and press enter.

After making a backup, navigate to the following key: HKEY_LOCAL_MACHINE > SYSTEM > CurrentControlSet > Control > Lsa

Modify the following key: “LmCompatibilityLevel” by double clicking on it, then change the value to 3

If that key does not exist:
right-click in the right pane, then select New > DWORD (32-bit value)
Type in: LmCompatibilityLevel
Double-click on the new value, and set it to 3 (Hexadecimal)

Now close Regedit. Wait for time for the changes to apply. Try Mstsc and see how it goes !

Windows 10 Pro

Go to start > run (Right click the Windows icon on the left hand side, select Run)

Type: “gpedit.msc” and press enter.

Go to Computer Configuration\Windows\Settings\Security Settings\Local Policies\Security Options – Network security: LAN Manager authentication level

set item to “Send NTLMv2 response only/refuse LM & NTLM”

(I ended up having to set it to Send NTLMv2 only).

Exit Gpedit.

Go to start > run (Right click the Windows icon on the left hand side, select Run)

Type: ” gpupdate /force” and press enter.

Gpedit on Windows 10 Home

ok, so when using Gpedit, there were some cool settings I wish I could use on my Windows 10 Home PC.

Can’t I get Gpedit on Windows home ?

Yes, you can.

You can download the Gpedit installer here

If you have 32-bit Windows (x86) then the setup should install smoothly without any problems and you should be able to access the Group Policy Editor through the Microsoft Management Console by going to Run –> gpedit.msc.

(You can check if you are 32 bit by going to Run –> Control,  Once in Control Panel go to “All Control Panel Items” and “System”. Here will be the name of your computer and a lot more into including what you need to know).

If you have 64-bit Windows (x64) then you will need some extra steps after running the installer. Follow the steps below after running the installer:

  1. Go to C:\Windows\SysWOW64 folder
  2. Copy the following folders and files from C:\Windows\SysWOW64 to C:\Windows\System32
    GroupPolicy“, “GroupPolicyUsers” and gpedit.msc.

You might be prompted to overwrite empty folders “GroupPolicy“, “GroupPolicyUsers

now go to the Widows 10 Pro instructions above and it will work the same.

Resources

some helpful links for you

https://social.technet.microsoft.com/Forums/ie/en-US/1383007d-677a-4e3e-83f0-a11869a2ac25/rds-server-remote-app-prompting-for-password-repeatedly?forum=winserverTS

https://www.tenforums.com/general-support/111678-local-security-policy-editor-not-found.html

https://www.itechtics.com/enable-gpedit-windows-10-home/

https://support.gotomyerp.com/portal/kb/articles/receiving-a-remoteapp-disconnected-upon-connection