Hi @Graham
Does this issue occur with other files on Dropbox (Such .docx document, .xlsx workbook) or with this .docx file that moved to other folders (not a Dropbox folder)?
Please go to ~/Library/Containers/
, remove the folder Microsoft Word. After remove the cache folder, restart Word.
Besides, this issue may be related to Dropbox, I would like to suggest you post a new thread on Dropbox support community to seek assistant.
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