Possible Duplicate:
ruby 1.9 ri problem
When I try to use Ruby's ri tool in a command prompt window to get help about classes, methods, etc. it seems to always fail. For example if I type:
ri Array
I get a message saying:
Updating class cache with 0 classes... Nothing known about Array
I am using Vista 64 with Ruby 1.9.1p243 (2009-07-16 revision 24175) [i386-mingw32] installed.
What should I do to configure ri to work?