I can't answer for anyone else, but I know Google users arrive here frequently, and I'm going to explain to them how I fixed this for my 600-page document filled with custom formatting, custom fonts and headers. I wasn't about to copy the contents into a second document and risk losing anything; the proofreading would take more time than I had going spare. Printing to PDF would have lost the hyperlinks scattered throughout the document. Images and constructions were integral to understanding what was being written about. In essence, "just do this" answers were not an option.
I set the permissions for t2embed.dll as others here note, but I can't say how much good it did. Word 2016 was alternating between giving me an error ("The export failed due to an unexpected error") and turning white and crashing. It crashed every time I tried to export, it was just a question of when. The program was producing a .TMP file in the directory I was exporting to, but after a few seconds it would vanish and progress would halt.
Eventually I decided to stick a camera up to my screen and film the output in the bottom-right. First it would enumerate the pages, then parse the links, and then slowly increment a counter for which page was being exported. This is assuming the program's interface hadn't crashed, so it took a few attempts. Eventually I found that the last number it was displaying before crashing was page 335. There was nothing strange about page 335, but replacing its contents with "removed to fix PDF export" caused the export to work fine.
Eventually, I copied the contents of page 335 to Notepad++ and changed all the quotation marks and apostrophes (which Word replaces with spicier versions) into normal ones. I copied it back as plain text and removed the hyperlinks. It worked. For some reason, that particular page had become corrupted and wouldn't export. Re-producing it worked.
+1 Because this sounds plausible. I'm going to try it and love the idea of filming the display to get determine which page it is puking on. – Eric Hepperle - CodeSlayer2010 – 2018-05-29T15:21:08.367