Upload button is inactive (grayed out)

New constributors are limited to 51 uploads. We don't know exactly what needs to happen to increase your upload limit, but it's suspected you will need to have at least 50 sales before your limit is increased. But that's just a guess on our part. The limit was put into place when contributors started uploading hundreds and even thousands of AI images that fell far short of Adobe's quality standards. When you have a few images accepted, you will be able to upload more images to maintain your 51 asset upload limit. 

That said, you did say that all your images were "accepted." Do you mean accepted, or simply submitted and thus under review? Or have your assets been reviewed and are now online for sale?

Where is it greyed out? Please show a screenshot.