Make sure you’ve got the cache set up correctly — “cache” folder in webserver root w/ write permissions (unless you modified the cache location in the code). Make sure twitter isn’t down (http://istwitterdown.com/). If you’re having more problems w/ it, let me know some additional details like what version of WordPress and PHP you have.
I am having the same problem. Do I have to CHMOD the folder with the plugins or the entire wordpress folder?
I was having the same problem and it seemed to coincide with making changes to other plugins. It would be working fine, I would go in a make a change to another plugin and it would stop working.
What I found that worked was to delete the contents of the cache folder and it would start working again.
also make sure the cache folder is writable with permission of 755
I released MyTwitter 2 today. It has a more stable backend. It’s WordPress 2.7 compatible (should support 2.5+, but I haven’t been able to test), and requires PHP 5.2 or newer.
http://wordpress.org/extend/plugins/mytwitter/
You’ve still got to watch the settings for the cache folder and as darrellosborn says, chmod it to 755.
