PNG files not showing in SharePoint 2010

One of our users made a discovery that was brought to my attention. Actually, it was two issues, if you could call them that. First, they reported that when they upload a .png file, it gets converted to a .jpg file. Second, the .png files were not showing up and giving the infamous red X.

Let’s start with issue number 1. This is by design in SharePoint 2010.

SharePoint automatically creates two JPG images every time you upload image to a Picture Library: they are the thumbnail image and the web preview image. They’re stored along with the original image in the Picture library.

No in-place conversion happens: the image is converted only once during the initial upload process.

SharePoint needs these extra images to display picture library thumbnail views and item forms correctly, quickly and not causing excessive server load. However, when you add the image to a page or image web part, it actually displays the .png file. So no conversion, no problem.

Now on to issue number 2. You upload a .png file to picture library. The thumbnail looks great, the preview image looks great, you copy the link and open it in a new tab and you get the big, fat, red X.

This is all because of the color profile of the image. If the web designer used PhotoShop or some other similar application, they may have saved the image with a CMYK color profile. Browsers can’t display CMYK images. Thus, the red X. The thumbnail and the preview are .jpg files (see above) so they look fine.

To solve the issue, just open up the image in your choice of editing software and save it as an RGB image. Re-upload the file and everything is fine!