Thanks for the try, Guessed- appreciate the help - but no, I do not use a shared drive. This is just a simple save on the hard drive of my PC. I cannot even save it to a flash drive - or any location on my computer, no matter which location I try. I couldn't even save it as a different type of file (PDF plain text etc).

I do not use, nor do I want to use, One Drive - I use Carbonite. But that only backs up once a day.

I did a workaround by copying the file in its folder, and then closing Word (not trying to save). Word, as usual, asked if I wanted to save changes and I hit "yes." So then I had the old file ("copy") and the edited one, which I then renamed upon opening word again.

But I did not want to keep doing that every time I wanted to save - which is every 15 mins or so for this manuscript. However, much to my surprise, something happened internally with Word and I was then able to save the MS the next time.

Yet - I just don't want this to happen again, and certainly don't want to go through those many steps each time I try to save a document. So... does anyone know why this occurred?

Thanks for the suggestions.