Windows Vista, Ruby v. 3.3.5
C:\\>gem install rmagick
Building native extensions. This could take a while...
ERROR: Error installing rmagick:
Download this rmagick-2.13.2.gem gem and save in you local.
Open the repository in cmd prompt where the gem file is located and run the following cmd
gem install rmagick-2.13.2.gem --platform=ruby --with-opt-lib=C:/ImageMagick-6.6.7-Q16/lib --with-opt-include=c:/ImageMagick-6.6.7-Q16/include
You can get rmagick to compile on Windows with the command:
gem install rmagick -- '--with-opt-dir="[path to ImageMagick]"'
There are three noteworthy things about this command:
You can have spaces in the path to the ImageMagick directory if you use this syntax. I think the path also doesn't care about forward or backward slashes, but I use backslashes.
You also have to make sure of two other things:
If ImageMagick isn't first in your system path, you'll get an "Invalid drive specification" error when extconf.rb tries to identify the ImageMagick version.
All that said, I've experienced failures to build with some version pairings of rmagick and ImageMagick. I was able to get ImageMagick 6.7.7 and rmagick 2.13.1 to build together on both Windows 7 and Server 2003.
On Windows, you should use the rmagick-win32 gem.
http://rmagick.rubyforge.org/install-faq.html#win
A simple google search yielded one very promising result: rmagick on windows. By the way, I guess you are using something like Ruby 1.8.5/1.8.7, but surely not 3.3.5 ( if you do, please let me join you in your time-travel adventures. We could be friends! )