VNC connections to macOS

by default, macOS uses Apple Remote Desktop Authentication. Some VNC Viewers like RealVNC can handle Apple Remote Desktop Authentication; unfortunately, TightVNC which we use in Royal TS has not yet implemented Apple Remote Desktop Authentication. 

The solution to this issue is to set a VNC password. To do this, please go to "System Preferences - Sharing". If Remote Management is turned on, turn it off. The reason for this is that you can’t have both Screen Sharing and Remote Management on at the same time:

Then enable "Screen Sharing" and specify who can share your screen:

All users: Any of your computer’s users can share your screen, except sharing-only users and guest users. If your Mac is connected to a network account server, anyone with an account on that server can share your screen using their network username and password.

Only these users: Screen sharing is restricted to specific users.

To set additional options for screen sharing, click "Computer Settings" and then select one or both of the following:

The default setting would be to enable "VNC viewers may control screen with password" and to configure a password as seen in the screenshot above.

You can find more information on this topic here:

Last but not least, you will have to configure the credential in Royal TS as follows:

Important: Make sure you do NOT set a username. The password you need to set in Royal TS is the password you set for the VNC viewers, NOT the Mac OS account password.

"Specified key is a known weak key for 'DES' and cannot be used"

If you receive the error message "Specified key is a known weak key for 'DES' and cannot be used" when connecting to macOS using VNC, there is also a workaround for that. It would appear that the Remote Core SDK used in our integrated TightVNC plugin causes this error message. Currently, the only know workaround is to use the external TightVNC Plugin.

VNC connections to Raspbian

by default Raspbian (the official Raspberry Pi OS) uses "UNIX-Password" as an authentication type. In order to connect to it using TightVNC you will have to change the authentication type in the RealVNC Server. To do this, go to the options of the RealVNC Server on your Raspi and change the authentication from "UNIX-Password" to "VNC-Password". You will then have to enter a VNC-Password. On your PC, you will have to specify credentials for this connection; leave the user name blank, and enter the new VNC-Password that you just created. 

If the connection still does not work after that, please check and see if "encryption" is enabled. If it is, please disable the "encryption" for the connection to work.

Encrypting a VNC connection using a Secure Gateway (SSH Tunnel)

Since having a non-encrypted VNC connection is not very safe, we strongly suggest using a Secure Gateway (SSH Tunnel) when using VNC connections. You can find out how to configure a Secure Gateway here: