I have the same problem. No podpress installed, running PHP 5.2.6 with GD enabled. Works fine on my local xampp site but on the remote server the option for small, medium, etc is greyed out. I temporary solved the problem by opening the image in photoshop and re-saving it, then uploading it again via WordPress. I have however still not found out what the difference between the two images is. Looks exactly the same in all settings and under information when right-clicking on desktop and selecting properties…