When trying to save a Word document in OneDrive, we get an error message implying that the file name is not valid. This issue occurs only when saving files from ...

We suggest the following fixes if you get This is not a valid file name error in Outlook when sending email: Remove invalid special characters from the file name ...

Since it won't open, it is either corrupt or possibly misnamed. Save the attachment to your file system and see if you recognize the file suffix (you may need to click Tools, Folder Options, View tab ...