What does it mean when a computer is 'greyed out' in Apple Remote Desktop? I've got several computers that I manage using Apple Remote Desktop. Sometimes I have issues connecting with some of them. I've noticed this most often happens when their computer icon is light purple (greyed out) as opposed to dark purple. 

Any ideas what this light purple means?
Per the ARD Administrators Guide (PDF), A "light purple" client status icon means that the client is offline (page 177).