When exporting a PDF from Word recently the page numbering got messed up. It should have been 1 of 21, 2 of 21, etc. Instead what I got was 1 of 2, 2 of 3, etc.

I just tried it now on what should be the same Word file with no changes (and no changes to my Options settings) and it correctly numbered the pages.

When this happened earlier I did a Save as Adobe PDF in Word and the page number came out correctly. Word had always displaying the numbering correctly.