Office files: comments, tracked changes and author fields

A Word, Excel or PowerPoint file is a ZIP archive of small text files. Some hold your content. Others hold a record of who worked on it and how.

Names

• Author and last modified by. Taken from the name set in Office, which is usually your full name.
• Company and manager. Filled in by many corporate installations.
• Comment authors. Each comment stores a name, initials and a time.
• A people list. Newer versions of Word and Excel keep a list of everyone who has commented, sometimes with an account identifier.

History

• Tracked changes. Every insertion and deletion is stored with the author and the time. Deleted wording is still in the file, in full, until the change is accepted. Sending a contract with tracked changes hidden from view, not accepted, has embarrassed more than one negotiator.
• Revision identifiers. Word stamps paragraphs with codes for the editing session they were typed in. Two documents sharing codes were edited from the same original.
• Total editing time and a revision count.
• Template path. The location of the template the document was based on, which can include a user name and a server or folder name.

Things that are easy to forget

• Hidden sheets, rows and columns in Excel. Their contents are in the file. A “very hidden” sheet does not even appear in the Unhide menu.
• Links to other workbooks. The path to the other file is stored, and so is a cached copy of the values it supplied.
• Speaker notes and hidden slides in PowerPoint.
• Printer settings in Excel, which can name the printer and the computer.
• Pictures. A photo placed in a document keeps its own metadata, including any GPS position. Cropping a picture in Office hides the rest of it but keeps it in the file unless you delete the cropped areas.
• Embedded files, such as the whole spreadsheet behind a chart pasted into a report.

How to check

Find hidden content lists hidden text, deleted wording kept by tracked changes, comments, hidden sheets, rows and columns, speaker notes, hidden slides, links to other files and embedded files. It reads the file in your browser and changes nothing.

How to clean

Remove metadata clears the author fields, company, manager, template path, editing time and custom properties, removes the preview picture and the people list, replaces the names on comments and tracked changes with “Author”, deletes the revision identifiers and printer settings, and cleans every picture inside the document.

It does not decide about your content. Comments, tracked changes, hidden sheets and speaker notes are pointed out, not deleted, because only you know whether they belong. In Word, accept or reject all changes and delete the comments you do not want. In Excel, unhide and delete sheets you do not mean to send.

The simple alternative

If the other person only needs to read the document, send a PDF, and clean that. A PDF made by “Save as PDF” still records the author and the program, but none of the editing history.