Apple Remote Desktop 3: Clients become unavailable if screen locked or curtained during login or logout
Symptoms
If you use Remote Desktop to take control of a client using Curtain mode, then log in or log out on the remote client, the control session will end and you will not be able to take control of the computer again until it is restarted. This occurs on client running Mac OS X v10.5 or later, and will also occur if you Lock the Screen of the client before taking Control.
Products Affected
Apple Remote Desktop 3.X
Resolution
Before logging out, close any windows with sensitive information, end the control session (and Unlock Screen if necessary).
Do not log out on the remote client while controlling it in Curtain mode.
Additional Information
Similarly, in Remote Desktop 3.0 to 3.2.2, do not use Lock Screen or Curtain mode on a Remote Desktop client if the client computer is at the login window. If necessary, use Curtain mode to enter the username and password in the login window, then end the Curtain mode session and start a normal (not Curtain mode) session to click the Login button. After the login process is finished, and the desktop and menu bar appear on the remote client, you may start a new Curtain mode session. This second issue is resolved in Apple Remote Desktop 3.3.
This document will be updated as more information becomes available.