I am aware that the final section break contains data/coding that can be causing problems in a document, and have used a number of times the technique of copying a document, minus the final paragraph, to remove corruption. I leave to the experts what all is actually going on behind the scenes, other than section characteristics such as headers/footers, margins, etc.

Once or twice I have found that a corruption was present only in one section of a multi-new-page-section document. More usually, especially in very long such documents (more than 100 pages) in which the corruption is pervasive, I have taken the precaution of copying each section's contents, minus it's section break, separately, pasting into the new document and inserting new section breaks.

I am curious as to the difference between these intermediate breaks and the final one. Is my assumption correct that an intermediate one could be harboring the problem?
1. If so, could there be a solution to problems without having to copy the entire document over?
2. If not, is it correct to assume that copying the individual sections would make no difference to the result?

That is an interesting question and I don't have experience of document corruptions at the section level but I will add some suggestions.
1. If you believe a corruption exists in a particular section break, you should be able to simply delete that section break. The attributes of the following section will flow backwards into the content in front of the section break you removed and theoretically remove the corruption. It would be interesting to note if the corruption you 'deleted' by this action is removed or transferred to the subsequent section break.
2. Rather than copying content to another file section by section, I would use a replace all function to replace all section breaks (^b) with a paragraph mark (^p) and then do a single copy/paste to a new document. This is something I often do to minimise clipboard complexity and adapt the page setups when I paste into other documents - I just don't do it for the purposes of removing corruptions.

In my experience over the past 10-15 years (touch wood), I've not seen a corruption that was only solveable by copying all to a new document. I have a hunch that the 'copy almost all to a new document' actually doesn't achieve anything with the docx format files (although it still might with doc format files) but I do agree that 25 years ago it was a useful practice that still gets passed on through folklore. I'm happy to be proven wrong but I just haven't seen enough corrupted files of late to be able to narrow corruptions down to the section break or final return.

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Andrew Lockton
Chrysalis Design, Melbourne Australia

The way I understand it, any section break can acquire corruption, in a similar way that a table or even a single paragraph may corrupt. See an overview in the article How can I recover a corrupt document or template - and why did it become corrupt?.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional

Thanks, Stephan. It's been a while since I had corruption from copying to a floppy, as cited in the reference; one less thing to worry about. Seems like only yesterday...

Whatever corruptions Andrew is seeing, I am happy not to change places with him. I have generally had good luck with the old method.

The most extraordinary document in my experience was a long government document in which our response had to be submitted. I reported this in a post a few years ago. Evidently it had been copied and pasted-into for many years. Opening the styles pane I found a long list of styles. I guessed over a hundred. It was, if I recall properly, more than 400. I printed out the styles list to show my colleagues; it was about 60 pages.

Needless to say, I did some weeding before we started.