We Could Not Merge the Changes Error Appears: OneDrive for Business Fix

When you try to save a file in OneDrive for Business, you may see the error: “We could not merge the changes. We saved a copy of your file instead.” This error occurs when two or more people edit the same Office file at the same time, and OneDrive cannot combine the edits. The file is saved as a separate copy on your computer, leaving the original file unchanged. This article explains why the merge fails and provides the steps to resolve the conflict.

Why the Merge Conflict Error Occurs

OneDrive for Business uses a feature called co-authoring to let multiple people edit the same Office file at the same time. When co-authoring works correctly, OneDrive merges each person’s changes into a single file. The merge fails when OneDrive cannot reconcile simultaneous edits made by different users. This happens most often when two users edit the same paragraph, cell, or slide at the exact same moment. OneDrive then saves a copy of your changes as a separate file with “(Your Name’s conflicted copy)” in the filename. The original file remains unchanged, and the other person’s edits are saved in the original. The error can also occur if sync is paused or if the file size exceeds 100 MB for Office files, which is the co-authoring limit.

Other triggers include a slow network connection that delays sync, a file that is checked out by another user, or a file stored in a location that does not support co-authoring, such as a SharePoint document library with required checkout enabled. The error message appears in the Office app, not in OneDrive itself, because the conflict is detected at the application level.

Steps to Resolve the Merge Conflict and Prevent It

Follow these steps in order. Start with the immediate fix, then adjust settings to reduce future conflicts.

Step 1: Locate the Conflicted Copy

1. Open File Explorer
   Navigate to the folder where the original file is stored. This is typically in the OneDrive folder under your user profile.
2. Look for the conflicted copy
   The filename will contain the phrase “conflicted copy” followed by your username and a timestamp. For example, “Budget 2025 (John’s conflicted copy 2025-03-15).xlsx”.
3. Open the conflicted copy
   Double-click the file to open it in the Office app. Review the changes that OneDrive could not merge. These are your edits that were not saved to the original file.

Step 2: Manually Merge Your Changes into the Original File

1. Open the original file
   In the same folder, open the original file (the one without “conflicted copy” in the name).
2. Compare the two files side by side
   Use the View tab in the Office app to arrange windows side by side. In Excel, click View > View Side by Side. In Word, click View > Arrange All. In PowerPoint, open both files and switch between them using Alt+Tab.
3. Copy your changes from the conflicted copy
   Select the content you added or changed in the conflicted copy, press Ctrl+C, switch to the original file, and press Ctrl+V to paste the content in the correct location.
4. Save the original file
   Press Ctrl+S. The file will sync to OneDrive and become available to other users.
5. Delete the conflicted copy
   After you confirm that all changes are in the original file, right-click the conflicted copy in File Explorer and select Delete. Then empty the Recycle Bin.

Step 3: Use Version History to Recover an Earlier Version

If the conflicted copy does not contain all your changes, or if the original file was overwritten, use version history.

1. Open the original file
   Open the file in the Office app.
2. Open Version History
   Click File > Info > Version History. A panel opens on the right side of the window.
3. Select a version
   Click a version that was saved before the merge conflict occurred. The file opens in a read-only view.
4. Compare and restore
   If this version contains the changes you need, click Restore at the top of the version panel. This replaces the current file with the selected version.

Step 4: Prevent Future Merge Conflicts

1. Communicate with your team
   Before editing a shared file, let others know you are working on it. Avoid editing the same section at the same time.
2. Check sync status
   Right-click the OneDrive cloud icon in the system tray. If sync is paused, click Resume syncing. If the icon shows a red X or a warning, follow the prompts to fix the sync issue.
3. Disable Files On-Demand if you have sync delays
   Right-click the OneDrive cloud icon and select Settings. Go to the Sync and backup tab and click Advanced settings. Under Files On-Demand, set it to Off. This forces all files to download, which can speed up sync on slow connections.
4. Require checkout on SharePoint document libraries
   If you manage a SharePoint site, turn on required checkout. This prevents two people from editing the same file at the same time. To do this, go to the document library, click the gear icon, select Library settings, then Versioning settings. Under Require Check Out, select Yes.

If the Error Still Appears After the Main Fix

OneDrive Shows “We Could Not Merge the Changes” on Every Save

This indicates a persistent sync problem. First, run the OneDrive sync troubleshooter. Open Windows Settings, go to System > Troubleshoot > Other troubleshooters, find OneDrive, and click Run. If that does not resolve it, reset OneDrive. Press Windows key + R, type %localappdata%\Microsoft\OneDrive\onedrive.exe /reset, and press Enter. OneDrive will restart and re-sync all files.

The Conflicted Copy Is Empty or Corrupt

If the conflicted copy contains no data or cannot be opened, use Version History as described in Step 3. If version history is also empty, check the OneDrive recycle bin online. Go to https://onedrive.live.com, sign in, and click Recycle bin on the left. If the deleted file is there, select it and click Restore.

Other Users See the Error When Editing the Same File

This confirms that the file is in a location that does not fully support co-authoring. Verify that the file is stored in a OneDrive for Business or SharePoint document library. Co-authoring is not supported in on-premises SharePoint 2013 or earlier, in files stored on a network drive, or in files with Information Rights Management (IRM) protection. Move the file to a supported location.

Co-Authoring vs Manual Merging: Key Differences

Feature	Co-Authoring	Manual Merging
How changes are combined	OneDrive merges edits automatically in real time	You copy and paste content from the conflicted copy into the original file
Number of users	Requires two or more users editing at the same time	Performed by one user after the conflict occurs
File types supported	Word, Excel, PowerPoint files only	Any Office file type, including those that do not support co-authoring
Conflict resolution	Automatic unless simultaneous edits conflict	Always manual; you decide which changes to keep
Time required	Instant	Several minutes per conflict

You now know how to find the conflicted copy, merge your changes manually, and adjust settings to reduce the chance of future merge errors. Next time you edit a shared file, check the OneDrive sync icon first to confirm sync is active. For persistent conflicts, turn on required checkout in your SharePoint document library to prevent simultaneous edits.