File Format & Compatibility

How to Save Microsoft Word 2010 Documents as DOCX Files

Maira Mehtab Sep 20, 2026 870 views

Question details

The user wants to save existing Microsoft Word files in the modern DOCX format instead of the older DOC format, and ensure new files default to DOCX.

Product: Microsoft Word 2010
Device & OS: not provided
Scenario: Upgrading older document formats to improve compatibility, reduce file size, and access newer Word editing features.
Observed behavior: Documents are currently saving or remaining in the legacy .doc format rather than utilizing the standard .docx format.

Before you start

Make sure you have write permissions for the document you want to convert, as read-only files cannot be converted and saved directly over the original version.

Solution 1Recommended

Convert an Existing DOC File to DOCX

Use the built-in Convert tool in Word 2010 to seamlessly upgrade a legacy document to the newer XML-based format.

This method replaces the older version of the document with a modern DOCX file, instantly unlocking new features like advanced formatting and smaller file sizes.

Open the existing file

Launch Microsoft Word 2010 and open the older .doc file that you wish to upgrade.

Navigate to the Info tab

Click on the 'File' tab in the top-left corner of the ribbon, then select 'Info' from the left-hand menu.

Convert the document

Click the 'Convert' button (if available). A prompt will appear explaining that the document will be upgraded to the newest file format. Click 'OK'.

Save your changes

Press 'Ctrl + S' or go to 'File' > 'Save' to save the newly converted DOCX document.

Compatibility Mode: Converting the file will remove the [Compatibility Mode] tag from the title bar, giving you access to all modern Word 2010 features.

Solution 2

Set DOCX as the Default Save Format

Configure Word 2010 to automatically save all newly created documents in the modern DOCX format.

Convert Word Documents with WPS Office

Seamlessly Convert DOC to DOCX with WPS Office

If you are dealing with legacy Microsoft Word formats, WPS Writer offers a fast, robust, and highly compatible way to open, edit, and save your documents as DOCX files without needing an older version of Microsoft Word.

1. Open your document in WPS Writer: Launch WPS Office and open the older .doc file you want to convert.
2. Access the Save As menu: Click the 'Menu' button at the top left corner, then hover over or click 'Save As'.
3. Select DOCX format: Choose 'Word Document (*.docx)' from the format options provided in the save dialog box.
4. Save the file: Select your desired save location and click 'Save' to instantly generate your modern DOCX file.

Fully compatible with Microsoft Word DOC and DOCX formatsFree, lightweight, and fast office suiteFamiliar user interface for a zero-learning-curve transitionBuilt-in batch conversion capabilities for multiple files

WPS Writer Save As Microsoft Word DOCX format

Frequently Asked Questions

Why should I save my files as DOCX instead of DOC?

DOCX is an XML-based format introduced by Microsoft that provides significantly smaller file sizes, better data recovery if the file gets corrupted, and superior compatibility with modern software compared to the older binary DOC format.

Will converting my DOC file to DOCX alter its original formatting?

In most cases, formatting remains perfectly intact. However, if the older document utilized highly specific legacy features, minor adjustments might occur as they are mapped to their modern equivalents in the DOCX format.

What if the 'Convert' button is missing in the Info tab?

If the Convert button is not visible under File > Info, the document is either already saved in the newest DOCX format supported by your Word version, or it is opened in a read-only state. You can always use 'Save As' and manually select DOCX from the format list.

Can older versions of Word open my newly converted DOCX file?

Users with Word 2007 or later can open DOCX files natively. Users on Word 2003 or earlier will need to download and install the Microsoft Office Compatibility Pack to open, edit, and save DOCX documents.

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