It is possible that you clicked "Block Images" in the right-click context menu while saving an image.

See:

• http://kb.mozillazine.org/Images_or_animations_do_not_load

You can use these steps to check if images are blocked:

• Open the web page that has the images missing in a browser tab.
• Click the website favicon (How do I tell if my connection to a website is secure?) on the left end of the location bar.

• Click the "More Information" button to open the "Page Info" window with the Security tab selected (also accessible via "Tools > Page Info").
• Go to the Media tab of the "Tools > Page Info" window.

• Select the first image link and scroll down through the list with the Down arrow key.
• If an image in the list is grayed and there is a check-mark in the box "Block Images from..." then remove that mark to unblock the images from that domain.

No, that didnt work! Its only been happening since I upgraded my firefox. I can upload to other sites like my company website. just seems to be when using facebook.

I'm having a similar issues. Can't upload images to Office Live Web site or see existing ones since I upgraded. Still works on my laptop as I haven't yet said yes to the Firefox update.

It stops working when trying to upload images as soon as I select my local drive. I also won't show existing images that I have uploaded.

Might be worth a shot at going back an issue of firefox......Facebook deny its them!