After installing Movable Type on the comment settings page I get the error:
No CAPTCHA provider available No CAPTCHA provider is available in this system. Please check to see if Image::Magick is installed, and CaptchaSourceImageBase directive points to captcha-source directory under mt-static/images.
On the system information page verify it shows your server has Image::Magick installed. If it is installed than you need to modify your mt-config.cgi file. The value of this configuration directive should be set to the absolute path on the filesystem to the images/catcha-source directory in mt-static.
Example
CaptchaSourceImageBase /path/to/mt/mt-static/images/captcha-source