I ran into a very strange problem in one of my WordPress sites. Some shortcode tags (Shortcode API) for a plugin did not work properly. In my case it was the ”NextGEN Gallery Version 1.9.3” plugin that couldn’t show a photo album, no photos where shown. Then I did some serious troubleshooting by looking into the source code of that plugin. I found out that the shortcode ”album” was misbehaving. It generated its output correctly but it were not shown on the webpage.
Then I began to realize that it was a case of shortcode conflict between my installed plugins. Two of my activated plugins used the same shortcode ”album”. After enabling and disabling my other plugins I found out that the ”Simple Facebook Connect Version 1.3 ” plugin caused the problem. Luckily I did not use that plugin any longer so I disabled and deleted it. If I really would have needed that plugin I would have to rewrite the source code of one of the plugins to change the shortcodes that conflicted.
This is something that WordPress users should be aware of, my guess is that there are a lot of conflicts between plugins that causes very random errors.