Microsoft Word has supported the DOCX format for well over a decade, yet many organizations still maintain archives of legacy .doc files. While these files remain usable, they introduce compatibility, security and collaboration limitations compared to the modern DOCX standard.

For Mac users, automating this conversion can be frustrating. Many VBA scripts found online rely on Windows-only components that simply do not work in Office for macOS. Fortunately, there is a clean, Mac-compatible approach that allows you to batch convert hundreds of DOC files in minutes directly inside Word.

This article explains the approach and what you should know before running any automation.

Why Convert DOC to DOCX?

DOCX files provide several advantages:

  • Better compatibility with modern Office features

  • Improved file integrity and reduced corruption risk

  • Smaller file sizes

  • Stronger support for collaboration and versioning

  • Improved compatibility with cloud platforms and document management systems

If your organization is preparing for cloud migration, document management integration, or long-term archiving, converting legacy DOC files is a practical first step.

The Challenge on macOS

Many VBA scripts use Scripting.FileSystemObject, which works only on Windows. Word for Mac does not support this COM object, causing scripts to fail immediately.

The correct solution on macOS is to use VBA’s built-in Dir function to enumerate files. This approach is fully supported, reliable, and significantly simpler.

Critical Disclaimer Before You Run Any Script

Always back up your data before running any automation.

Even well-tested scripts can behave unexpectedly due to file corruption, permission issues, naming conflicts, or environmental differences. Before running any batch conversion:

  • Copy your entire source folder to a backup location

  • Confirm that the backup opens correctly

  • Test the script on a small sample set first

Automation should never be your only copy of important business or legal documents.

How to Open the VBA Editor in Microsoft Word for Mac

Before inserting the script, you must open Word’s VBA editor:

  1. Open Microsoft Word.

  2. From the top menu bar, click Tools.

  3. Select Macro → Visual Basic Editor.

  4. In the VBA window, click Insert → Module.

  5. A blank module window will appear where you can paste the script.

You can now paste the macro into this module.

What the Script Does

The Mac-compatible script:

  • Scans a folder for .doc files

  • Opens each file in Word

  • Saves it as a .docx file in a new folder

  • Closes the document without altering the original

  • Skips existing .docx files automatically

The process is fast, repeatable, and does not require any third-party tools.

The VBA Script (Mac Compatible)

Below is the exact script used for batch conversion. Make sure you replace the example source folder and output folder with the file path on your computer.

Sub BatchConvertDOCtoDOCX_Mac()
Dim SourceFolder As String, OutputFolder As String
Dim fileName As String
Dim fullInPath As String, fullOutPath As String
Dim doc As Document

SourceFolder = "/Users/johnnyappleseed/Desktop/Old format/"
OutputFolder = "/Users/johnnyappleseed/Desktop/New format/"

' Enumerate ONLY .doc (not .docx)
fileName = Dir(SourceFolder & "*.doc")

Application.ScreenUpdating = False

Do While fileName <> ""
' Safety: skip .docx if it somehow matches (rare, but defensive)
If LCase$(Right$(fileName, 5)) <> ".docx" Then
fullInPath = SourceFolder & fileName
fullOutPath = OutputFolder & Left$(fileName, Len(fileName) - 4) & ".docx"

Set doc = Documents.Open(FileName:=fullInPath, ReadOnly:=True, AddToRecentFiles:=False)

' wdFormatXMLDocument = .docx
doc.SaveAs2 FileName:=fullOutPath, FileFormat:=wdFormatXMLDocument
doc.Close SaveChanges:=False
End If

fileName = Dir()
Loop

Application.ScreenUpdating = True
MsgBox "Conversion Complete!", vbInformation
End Sub

When This Approach Is Most Useful

This solution is ideal for:

  • Law firms migrating legacy matter archives

  • Creative agencies consolidating historical project files

  • Construction and engineering firms modernizing bid and plan records

  • Nonprofits cleaning up document repositories

  • Small businesses preparing for cloud storage or DMS platforms

Operational Best Practices

To avoid issues:

  • Use dedicated source and output folders

  • Avoid running the script directly on your only copy

  • Keep file names simple when possible

  • Close other Word documents during execution

  • Allow the script to finish without interruption

Final Thoughts

Batch converting DOC files to DOCX on a Mac does not require third-party software or complex tools. With a properly written VBA macro and a cautious backup process, you can modernize years of documents in a controlled, auditable way.

If your organization is managing technical debt in document systems, this type of structured cleanup is a small investment that pays long-term dividends in reliability, compatibility, and operational efficiency.