Loading files from a different partition

Question

I'm working at C:\(...)\Desktop, and I need to require my scripts at G:\scripts. I tried to change the $LOAD_PATH:

$LOAD_PATH << 'G:\\scripts'
require 'filename'

and also the argument of require:

require 'G:\\scripts\\filename'

but I always get

C:/Ruby193/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': cannot load such file -- dir_iterator (LoadError)
from C:/Ruby193/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from a.rb:2:in `<main>'

It works well if the directory is on C:\ partition. What's happening here?