Images and text in the header and footer will be dimmed when you are working
in the document layer (and vice versa when you're working in the
header/footer layer). They will print correctly, however.
If an image anchored to the header/footer appears dim even when you have the
footer open for editing, it may actually be formatted as "washout" or
"watermark." Some wrapped images in the header/footer may appear dimmed even
in Print Preview but will print correctly.
This is the way Word works; if you want a document that is displayed
electronically exactly as it will print, you need to create a PDF.