Thread: Header ad 468x60 - cannot upload

Header ad 468x60 - cannot upload

Whenever I upload a 468x60 header image and click "Insert to post", the window dissappears and nothing uploads. There is no preview of the image in General Settings > Advertising like there is under General Settings > General for the logo. The image is saved to image library but does not show.
I am not using an affiliate link it is just a banner image. I have tried linking to a URL as well and it is the same result. Enable ad is set to "Yes" but have switched to no as I don't want to look at an Appthemes banner. I have also tried using the browser uploader as suggested if having problems.
Can anyone help with this issue please? It's driving me mad.
Thanks,
Josh