Q I had an inexplicable experience with Word 2011 and Mail 6.0: a colleague sent a Word .doc document from his Windows PC. When I opened it from within Mail, the content shown was from an older but similar file that he had sent previously. Another colleague using Word 2004 saw the correct content instead. What has happened?

A Save that enclosed file to your Documents folder then open it using Word, just to confirm that that on your Mac is the older version. If it is, the most likely explanation is that confusion has occurred due to a bug or file system error, and Mail has somehow picked up the older version of the document rather than that enclosed. Try checking your startup disk using Disk Utility, to confirm that there are no disk errors on it: for instance, the disk directory could be pointing incorrectly at the older rather than the newer file.

Mail keeps its attached files in sub-folders named Attachments within the structured tree inside the respective mailbox folder, in ~/Library/Mail/V3 (older versions may use V2). As far as I can tell, it uses the same mechanism for fetching the file when you open it from within Mail, as when you save the file outside your mailbox. Therefore any difference between those suggests that you might have a duplicate Attachments folder, or another error that could cause Mail to become confused.

Although it is unlikely to account for this problem, Word native .doc format can carry an extraordinary amount of overhead, in the way of old versions of documents, etc. If someone has used an earlier version of a doc and then changed the content to create a newer doc, it is common for a lot of the original content to remain in the doc file; this can be reflected in the file size.

One way to force Word to do a bit of housekeeping and clear out the old stuff is to Save As. But in many cases, that is only done with the original template, and not when the content has been replaced. When a different version of Word, or an application that relies on a third-party library to access Word format files, is used to open such a file, it could misinterpret the content and show older material from within the file.

If other users have had similar problems, please let us know what caused them.

Comments This remains a completely enigmatic problem, and no matter how hard I try, I am unable to simulate or imagine conditions which could account for this. Perhaps it is best to put it down to cosmic rays?!

Updated from the original, which was first published in MacUser volume 28 issue 24, 2012.