I tried a few different plugins, they all make use of tags like [audio:file.mp3] or [rating:3.5] - when i put this tags in my posts nothing happens. They are not replaced by the actual content. I tried this in my localhost and my server and the same thing happens. Then I thought maybe my theme (started from scratch) was missing tags, but I ran the same plugins in 5 different themes (including the default and classic) and nothing happened either it just prints the tags as if it were HTML. So it's not the server configuration, it's not the theme, it's not the WP version, I installed it several times, so it's not the installation.
I also checked for Plugin Hooks to see if they were missing. I even downloaded plugin themes so they already had all the Hooks and nothing.
What could it be?