Word legal blackline solution

When I review student work, I use Word's legal blackline function to compare the original version to the new version. I have previously written about this (here), but recently I had a problem where I was unable to see the changes in the documents I was attempting to compare.

It seemed that nothing I did made a difference to the view: the comparison document remained stubbornly blank, except for a red stripe down the left-hand margins the paragraphs which had changed. And seeing as this was nearly every paragraph, but without indicating WHAT had changed, what I was seeing was effectively useless.

It was like the legal blackline function had simply fallen off a cliff. I Google searched, I trouble-shot via the Microsoft help and support pages, but could find nothing on the problem. I wondered if this was related to an Office 365 update around Christmas time, but found no other users appeared to be reporting problems.

And then I found the answer: when I created a comparison window, under the review ribbon, the default markup view had been set to "Simple Markup". A quick change to "All Markup" solved the problem.

While I have no idea why that would have changed, hopefully the next time I encounter this problem I will remember to check this FIRST, and save myself hours of faffing about!

Sam