Thanks for the response. All of those ended up with the same response from word as saving as a docx file. It gives the spinning wheel, eventually says word is not responding and gives the option to close or wait. The other odd thing is that two other people have been able to add their edits to the document, so presumably this is not something that everyone is experiencing. I'll try to open and re-save it from my work PC and see if that makes any difference at all.