Enable Mac OS X Leopard Remote Desktop for VNC via SSH

If you have SSH access to your Mac, you can remotely enable Remote Desktop. However, if you want to VNC into the Mac, you'll need to set a VNC password and turn VNC on. The following huge command turns on Remote Desktop, enables VNC, and sets the password to password.

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -activate -configure -access -on -restart -agent -privs -all -setvnclegacy -vnclegacy yes -setvncpw -vncpw password

However, the last part doesn't seem to work, so you can run:

sudo nano /Library/Preferences/com.apple.VNCSettings.txt

and put this as a single line:

6755221DFCC7B786FF1C39567390ADCA

which is the encoding of "password". Now use SSH tunnels, connect, and it should work. You can then change the password via system Preferences to a more secure one.

To turn off Remote Desktop run:

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/Resources/kickstart -deactivate -configure -access -off

Apple Remote Desktop and the 3.889 Error

If you have Mac OS X 10.5, you can run "Screen Sharing" which is Apple's version of VNC. However, if you simply enable it and try to connect, you will get an error such as:

VNC server supports protocol version 3.889 (viewer 3.3)
VNC connection failed: Incompatible Version.

This will also appear as similar errors about incompatible security and so forth from various other VNC viewers; the above error is xtightvncviewer on Ubuntu Linux.

The cause of the problem is that Apple's Remote Desktop supports additional features in security that are not part of the normal VNC protocol; to fix it, click "Computer Settings" under Screen Sharing on the Sharing page of System Preferences, and set a password for VNC viewers. Then it will work.