This has happened to me in the past as well and WP would display only the image icon, but I have found a "work around" (at least it worked for me).
Try uploading only from the Media tab, if your editing a Post and try to upload using Add Media/Upload Files you will get the http error in red.
Also go to file manager from cpanel and delete any duplicate images uploaded with the same file name and try to re-upload them using only the WP Media Tab.
-I have found that after uploading and receiving the http error, WP has created multiple images with different sizes such as "wood.jpg, wood1.jpg, wood2.jpg etc.."
One more suggestion: If the image doesn't display after uploading the new image from the Media Tab, right-click the page and select reload/refresh page.
-I hope this helps someone
Try uploading only from the Media tab, if your editing a Post and try to upload using Add Media/Upload Files you will get the http error in red.
Also go to file manager from cpanel and delete any duplicate images uploaded with the same file name and try to re-upload them using only the WP Media Tab.
-I have found that after uploading and receiving the http error, WP has created multiple images with different sizes such as "wood.jpg, wood1.jpg, wood2.jpg etc.."
One more suggestion: If the image doesn't display after uploading the new image from the Media Tab, right-click the page and select reload/refresh page.
-I hope this helps someone