If you do edit the file and save it, where are the changes you made?
The email still contains the original attachment, and opening it again brings up the unedited document.
Fortunately, you might still find the updated document on yourhard drive.

Here’s where to look.
To find that folder’s common location:
In theFinder, selectGo to Folderunder theGomenu.
The keyboard shortcut isCommand+Shift+G.

punch in the following path into the window:
~/Library/Containers/com.apple.mail/Data/Library/Mail Downloads/
ClickGo.
Files you have opened in Mail will be in sub-folders.
SelectGroup By>Date Createdfrom the menu.

Some versions of macOS may call the menuArrange By.
To sort without grouping, Make surelist viewisenabledin Finder for theMail Downloadsfolder.
Click again to reverse the sort order.

In Mail, selectPreferencesunder theMailmenu.
The keyboard shortcut isCommand+,(comma).
Under theDownloads Foldermenu, clickOther.

Navigate to the folder you want to use and chooseSelect.
It will, however, remove any files associated with deleted messages.
you’re free to prevent this by changing the setting underRemove unedited downloads:toNever.






