Yep you’re right. I’ve never seen something like this happen before. I think I may have spent well over 30 minutes trying to figure this out and I have no idea why it’s not working. I tested on my own site (The Guru Theme demo) and it works fine, so I don’t think it’s a Theme Issue.
The only thing I can thing of is another plugin or custom code disabling the Featured Image option. I would try and disable some of your plugins, then test the Featured Image to see if it will work. If it does, then it’s definitely a plugin issue. If it doesn’t, then there must be a setting somewhere within the site or custom code that prevents the image from showing.
I did some Google searches but didn’t find anything related to this issue. Closest thing I could find was this – http://wordpress.stackexchange.com/questions/18096/featured-image-meta-box-not-showing-up They’re saying if you use WordPress MU then you would need to change a setting in the Network Admin. The Network Admin is only available to the “Super Users” according to one of the commenters. I’ve never used WordPress MU so I’m not familiar with it….I’m also not even sure if that’s the issue. But definitely try disabling the plugins to see if the option is available again.
Also check any custom code that you may have added in the theme, as that could also disable the feature in some cases.
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