Sorry Paul - I should have answered sooner. For your suggestions - I can't try the Office repair one, because out IT group removed that functionality from the installation we see.

I tried fixing the Word document, that didn't work either. From what I can see from trial and error, there is an issue with the .GoTo method when it is called from MS Access. It simply doesn't work - it crashes Word without an error message, and it doesn't even get to checking to see if the bookmark is valid or not. Interestingly, it does not seem to work in Office 2016, either. I took it home to try, and while it doesn't crash Word, it cause Word to hang and become completely unresponsive.

I can't use this at this point:
because I do need to navigate to the bookmark, and move around after doing so. That code does work elsewhere, though.

After much searching, I did find a workaround that doesn't use the GoTo:

and it seems to do the trick. Thanks for all your suggestions.