I have cygwin version 3.4.10-1.x86_64 installed on my windows 7 machine. Until recently I could call man on any topic, e.g. $ man man; $man ls, etc. and the relevant man page would be displayed. I then ran setup-x86.exe and noticed that in the View section of the select packages screen there was a dropdown named “Unneeded”. Possibly foolishly, I selected these and then next and let the package manager go to work. Now I get no output whatsoever. As far as I can tell all other applications I have installed and use work as I expect.