I am having the same issue it seems as many people on here. I am able to upload images, they appear in my media library but the thumbnails and the images themselves are broken. If I try to edit them they appear, are editable but then disappear again.
I have followed all the advice I can find on here:
- deactivating all plugins to see if this resolves the problem. If this works, re-activate the plugins one by one until you find the problematic plugin(s).
- switching to the Twenty Eleven theme to rule out any theme-specific problems.
- resetting the plugins folder by FTP or PhpMyAdmin. Sometimes, an apparently inactive plugin can still cause problems.
- re-uploading the wp-admin and wp-includes folders from a fresh download of WordPress.
- I have also checked permissions and changed where necessary on the wp-admin and wp-content folders
Any more things I can try? I am going quietly crazy.....