HTTP error and 1px x 1px image display

When I upload images, I get an annoyingly nondescriptive HTTP error. However, the image uploads fine.

When I put those images in a post it comes out with the width and height for both the [caption] and <img> as 1px. I can change them manually, but the problem comes in when it’s in the featured image and still shows up as 1×1…then I can’t edit the height/width of display. (Is there a plugin that can? That would provide a fix for this.)

So why is this? Tried deactivating all plugins, it still did not work.