I have noticed this problem occassionally but now decided to report problem with non-display of Google AdSense link units. I will upload a screenshot of the problem image URL to Google AdSense Support. Their contact form do not provide for uploading of images (screenshots) so I have to upload it here, get the image URL and put the screenshot URL into the message in the AdSense contact form.
I will of cause mention my displeasure at the display of blank space and that if for some reason the link units cannot be displayed, they should at least not leave a blank space.
We will see what Google AdSense have to say about this.
