How to Prevent Office File Conflicts During OneDrive Migration

When you move Office files to OneDrive, you may see conflict copies named with your device name and a timestamp. These conflicts happen when two people edit the same file at the same time or when a file is open during migration. This article explains how to set up OneDrive sync settings, use file checkout in SharePoint, and schedule migrations to avoid these conflicts. You will learn specific steps to prepare your files, configure your environment, and run the migration without generating unwanted conflict versions.

Why Office File Conflicts Occur During OneDrive Migration

Office file conflicts in OneDrive happen when two users edit the same file at the same time and OneDrive cannot merge the changes. During migration, files are being copied from a local drive, network share, or another cloud service to OneDrive. If a file is open in an Office application while it is being migrated, the sync engine may detect a version mismatch and create a conflict copy. The conflict file usually has a name like “Report (User-PC-2025-03-14T10-30-00).docx”.

The root cause is the lack of a locking mechanism during migration. OneDrive does not block edits to files that are being uploaded. When the sync engine encounters a file that changed after the upload started, it treats both versions as valid and saves both. This is a safety feature, but it creates confusion for users who must manually merge the conflict copies.

Another common cause is that the migration tool or script runs while files are still open in Office applications. Even if a user is not actively editing, having a file open in Word, Excel, or PowerPoint can cause the sync engine to see a locked file and fail to upload it. When the file is closed later, the sync engine uploads it, but if another user already uploaded a newer version, a conflict appears.

Steps to Prevent Office File Conflicts During OneDrive Migration

Step 1: Prepare Files and Notify Users

1. Identify all Office files in scope
   Use a migration assessment tool like Microsoft Migration Manager or a third-party scanning tool to list all .docx, .xlsx, .pptx, and other Office files. Note which files are shared with multiple users.
2. Notify users of the migration window
   Send an email at least 48 hours before migration. Instruct users to close all Office files and sign out of Office applications during the migration window. Specify the exact start and end times.
3. Check for open files on source locations
   Use a script or tool to verify no files are locked by Office processes. On Windows, you can use the openfiles command in an elevated Command Prompt: openfiles /query /v | findstr .docx. Resolve any locks before migration.

Step 2: Configure OneDrive Sync Settings

1. Pause OneDrive sync on all target devices
   Right-click the OneDrive cloud icon in the system tray and select Pause syncing > 2 hours or 24 hours. This prevents the sync engine from writing files to OneDrive while migration is in progress.
2. Set Files On-Demand to free local space
   In OneDrive settings > Sync and backup > Advanced settings, turn on Files On-Demand. This ensures that migrated files are not immediately downloaded to every device, reducing sync conflicts during the initial upload.
3. Exclude unnecessary folders from sync
   In OneDrive settings > Account > Choose folders, uncheck folders that do not need to be synced during migration. Only select the target folders where files will be migrated.

Step 3: Use SharePoint Checkout for Collaborative Files

1. Enable Require Checkout on the target document library
   Go to the SharePoint document library where files will be migrated. Click the gear icon > Library settings > Versioning settings. Under Require Checkout, select Yes. This forces users to check out a file before editing, preventing simultaneous edits.
2. Check out all files before migration
   Use a PowerShell script or the SharePoint UI to check out every file in the target library. This locks the files so that no one can edit them during migration.
3. After migration, check in all files
   Run a script to check in all files with a comment like “Migrated from source”. This makes the migrated version the official version and clears the lock.

Step 4: Schedule Migration During Off-Peak Hours

1. Identify low-activity periods
   Analyze your organization’s usage patterns. For most businesses, this is between 10 PM and 6 AM local time. Use Microsoft 365 usage reports in the admin center to confirm.
2. Run the migration tool during the low-activity window
   Configure your migration tool to start at the beginning of the off-peak period. For Microsoft Migration Manager, set a schedule in the migration settings. For third-party tools, use the scheduler feature or a PowerShell script with Start-Sleep.

Step 5: Use Versioning to Restore Original Files if Conflicts Occur

1. Enable major versioning on the target library
   In SharePoint library settings > Versioning settings, set Create major versions to Yes. Keep at least 100 versions to allow rollback.
2. After migration, review version history for conflict files
   Open the document library and select a file that has a conflict copy. Click the file name > Version history. Look for the version marked “Conflict” or with a timestamp matching the migration window.
3. Restore the correct version
   Click the three dots next to the version you want to keep and select Restore. Delete the conflict copy after confirming the correct version is active.

If Office File Conflicts Still Appear After Migration

OneDrive Created a Conflict Copy Named with My PC Name

This happens when a file was open in an Office application during the upload. To fix it, close all Office applications and check the conflict copy. Open both the original and the conflict file. Use the Compare feature in Word or the Merge workbooks feature in Excel to combine changes. After merging, delete the conflict copy from the OneDrive folder. To prevent this in future migrations, always ensure all Office applications are closed before starting the migration.

Multiple Users Edited the Same File During Migration

If the migration spans several hours and users are actively working, conflicts are unavoidable without checkout. To resolve this, use the See what changed option in OneDrive. Right-click the conflict file and select See what changed. OneDrive opens a diff view showing which lines or cells differ. Manually merge the changes into the original file and delete the conflict copy. For future migrations, enable Require Checkout on the target library before starting the migration.

Migration Tool Created Duplicate Files Instead of Conflicts

Some migration tools create duplicate files if they cannot determine the correct target path. Check the migration log for errors like “File already exists”. In the OneDrive or SharePoint library, sort by the Modified date to find duplicates. Compare the file sizes and metadata. Delete the older or smaller duplicate. To prevent this, use a migration tool that supports deduplication, such as Microsoft Migration Manager with the Skip if exists option enabled.

OneDrive Sync vs SharePoint Checkout: Conflict Prevention Methods

Item	OneDrive Sync	SharePoint Checkout
Best for	Personal files and small teams with low edit frequency	Collaborative document libraries with multiple editors
Conflict prevention method	Pause sync, schedule off-peak hours, close Office apps	Require checkout locks files until check-in
Recovery after conflict	Manual merge using Compare or See what changed	Version history restore
User experience impact	Low — users can still edit if sync is paused	High — users must check out/in files
Automation level	Manual steps required per device	Scriptable with PowerShell

You now have a clear process to prevent Office file conflicts during OneDrive migration. Start by notifying users and closing all Office files. Then pause OneDrive sync and enable Require Checkout on the target SharePoint library. Schedule the migration during off-peak hours and use version history as a safety net. For an extra layer of protection, run a PowerShell script to check out all files in the target library before migration and check them in after migration completes.