This would seem to be a bug. It is an issue that I experience intermittently but regularly.
Over an number of days, I'm currently printing off a number of copies of an illustrated booklet that I've created using Publisher. On some days, when I open the Publisher document, not all of the pictures in the publication open in full resolution - some, but never all of them (so far) might be blurry. All images in my booklet are set to be linked, not embedded. This has caused a fair amount of wasted expense on printouts as I have had to bin the pages with blurry images. (That's not cheap as I print on glossy paper).
As an interim workaround, upon opening the document for that day's printouts, I now go through the booklet page by page to visually check whether each image is sharp or blurry - this is usually failry easy to spot as when I move to a new page I can momentarily see an initially blurry image suddenly 'snap' into the high resolution version.
