I searched for this question and could not find a similar one for my problem. So, here goes...
I moved to a new EC2 server (Linux 2) and have installed everything I thought was needed. However, now when I login to the back end of my Wordpress sites, I am no longer able to "edit" (crop, resize, etc.) images - like a featured image. No image is shown when I click "Edit Image". I have tried turning off all plugins... no change. Any suggestions?
Thanks!
Thanks to @JohnRotenstein, I copied this question to the Wordpress exchange, and it was immediately, and correctly, answered. The problem was the GD was not installed for PHP. I installed it, and voila!
Thanks everyone!