Hi, I started using YSlow and I noticed that I haven`t got expire headers on my static files. So I did a little research what is that and how to add it and tried to turn it on from the .htaccess file. But the problem is that when I put the code in the file apache returns me a 500 error. And I started thinking that the problem is from Rails.
Do you have any ideas? Thanks in advance.
A 500 Internal Server Error could mean there is a problem in Apache configuration. You mention editing the .htaccess file, which leaves me thinking something is wrong with your .htaccess file; a typo, a syntax error, an attempt to load a module that's not available and things like that. You may want to inspect Apache error logs to find out what's wrong with the .htaccess file.
You could try with a different server (e.g. WEBrick). Just start your app in development mode and check the headers with Firebug? In that way you can eliminate the Apache dependency for now.
What about using nGinx? http://effectif.com/articles/configure-the-expires-header-on-your-rails-site-with-nginx