Backup Fails with "Cannot Back Up Microsoft OneDrive Cloud File"

Backup Fails with “Cannot Back Up Microsoft OneDrive Cloud File”

Category: Acronis Troubleshooting | Cloud Storage & OneDrive Issues
Priority:HIGH
Last Updated:November 2025

Problem

Acronis backups fail when attempting to back up Microsoft OneDrive files on systems using the “Files On-Demand” feature. This feature creates NTFS reparse points (symbolic links) instead of storing actual file content locally, causing backup applications to encounter errors when trying to read and back up these placeholder files.

The issue affects entire machine backups and file-level backups that include OneDrive directories. Since many modern Windows installations enable Files On-Demand by default to save disk space, this has become an increasingly common backup failure scenario.

Symptoms

Primary Error Message

When running a protection plan that includes OneDrive files or folders, the backup fails with:

Detailed Error Examples

Error Pattern 1 - Unknown Error:

Error Pattern 2 - Cloud Operation Not Supported:

Error Pattern 3 - Reparse Point Error:

File Explorer Indicators

In Windows File Explorer, OneDrive files showing these icons will cause backup failures: - ☁️ Cloud icon - File is online-only (not stored locally) - Gray X - File not synced locally - Placeholder file - Reparse point only, no actual content

Files with these icons will back up successfully: - ✅ Green checkmark - File is locally available - 🔄 Blue sync arrows - File is syncing (may succeed or fail depending on timing)

Backup Behavior

• Backup may start successfully

• Failure occurs when encountering first OneDrive reparse point

• Error appears consistently if OneDrive has online-only files

• Entire backup fails (not just OneDrive files)

• Issue affects both scheduled and manual backups

• Problem persists across backup retries without configuration changes

System Configuration

This issue typically occurs on systems with: - Windows 10 or Windows 11 - Microsoft OneDrive installed and active - Files On-Demand feature enabled (default on modern Windows) - OneDrive folder included in backup selection - Backup type: Entire Machine, or File-Level including user profiles

Solution

Choose one of the following solutions based on your requirements and environment.

Solution 1: Disable Files On-Demand (Recommended for Complete Local Backup)

This solution downloads all OneDrive content locally, allowing Acronis to back up actual files.

✅ Choose this solution if: - You have sufficient local disk space - You want OneDrive files included in local backups - You need complete offline access to OneDrive files - You work frequently without internet connectivity - You want comprehensive disaster recovery capability

Prerequisites: - Adequate free disk space (check OneDrive settings for total size needed) - Stable internet connection for downloading files - Time for initial sync to complete (varies by data size)

Step-by-Step Instructions

1. Access OneDrive Settings:

1. Locate the OneDrive cloud icon in the system tray (bottom-right corner of taskbar) If not visible, click the up arrow (^) to show hidden icons

2. Click the OneDrive icon (cloud symbol)

3. Click the ⚙️ Settings gear icon (or three dots ⋮ menu)

4. Select Settings from the menu

2. Disable Files On-Demand:

1. In the OneDrive Settings window, select the Settings tab

2. Locate the section labeled Files On-Demand

3. Uncheck this option:

   ☐ Save space and download files as you use them

4. Click OK to save changes

3. Wait for Download to Complete:

OneDrive will automatically begin downloading all cloud-only files: - Monitor progress via the OneDrive system tray icon - Initial sync time varies based on: - Total OneDrive content size - Internet connection speed - System performance - Typical times: - Small (< 10GB): 10-30 minutes - Medium (10-50GB): 1-4 hours - Large (50-200GB): 4-24 hours - Very large (> 200GB): 24+ hours

4. Verify Download Status:

Check that files are now stored locally: 1. Open File Explorer 2. Navigate to OneDrive folder (typically C:\Users\[YourName]\OneDrive) 3. Look for ✅ green checkmarks on files (indicates local storage) 4. Verify no ☁️ cloud icons remain (would indicate online-only)

5. Test Backup:

1. Run your Acronis backup plan manually

2. Verify backup completes successfully

3. Check backup log to confirm OneDrive files were included

4. Validate backup size increased (should reflect OneDrive content)

Important Considerations

Disk Space Requirements: - Check available space before disabling Files On-Demand - OneDrive shows total size in Settings → Account - Ensure at least 20% additional free space beyond OneDrive size

Ongoing Sync: - Files remain synced to OneDrive cloud - Changes sync bidirectionally (local ↔︎ cloud) - Local files are now backed up by Acronis - Files are protected both locally (Acronis) and in cloud (OneDrive)

Performance Impact: - Initial download may slow system temporarily - Ongoing sync uses minimal resources - Local files available instantly (no download delay)

Solution 2: Exclude OneDrive from Backup (Recommended for Space-Constrained Systems)

This solution keeps Files On-Demand enabled and excludes OneDrive from Acronis backups.

✅ Choose this solution if: - You have limited local disk space - OneDrive already provides cloud backup/versioning - You want to keep Files On-Demand benefits - You primarily access files while online - You backup other critical data separately from OneDrive

Benefits: - Maintains disk space savings from Files On-Demand - Backup completes successfully (excluding OneDrive) - OneDrive files remain protected by Microsoft’s infrastructure - Faster backup operations (less data to process)

Step-by-Step Instructions

1. Open Backup Plan:

1. Launch Acronis Cyber Protect or Acronis Agent

2. Navigate to Backup or Protection Plans

3. Locate the failing backup plan

4. Click Edit or Modify

2. Access Exclusion Settings:

1. Expand Backup options or Advanced settings

2. Look for Exclusions or File filters section

3. Select Exclusions tab

3. Add OneDrive Exclusion:

Add these paths to the exclusion list:

For Personal OneDrive:

For OneDrive for Business:

For Both (Recommended):

Path Pattern Explanation: - * = Matches any characters (wildcards) - ** = Matches all subdirectories recursively - Use \OneDrive*\ to catch both personal and business OneDrive folders

4. Save Configuration:

1. Click OK or Apply to save exclusions

2. Click Save or Apply on the main backup plan

3. Review the summary to confirm exclusions are listed

5. Test Backup:

1. Run the backup plan manually

2. Verify backup completes without OneDrive errors

3. Check backup log: Should show successful completion Should indicate excluded items (OneDrive paths)

4. Confirm backup size is appropriate (smaller without OneDrive)

Verification Steps

Confirm Exclusion is Working:

Review the backup log file for entries like:

Check Backup Content:

1. In Acronis console, view backup details

2. Browse backup content

3. Verify OneDrive folders are not present

4. Confirm other user data is included

Prevention

Pre-Deployment Planning

1. OneDrive Assessment

Before deploying Acronis, assess OneDrive usage:

• Survey how many users have OneDrive enabled

• Determine average OneDrive storage per user

• Identify whether Files On-Demand is standard configuration

• Calculate disk space impact of disabling Files On-Demand

• Decide on organization-wide approach (Solution 1 vs. 2)

2. Backup Strategy Documentation

Create clear policy:

3. User Communication

Inform users about: - Why OneDrive settings may change - Disk space implications - Backup coverage (what is/isn’t backed up) - Expected sync times if disabling Files On-Demand

Standardized Configurations

Group Policy for Files On-Demand:

For enterprise deployments, use Group Policy to standardize:

Location: Computer Configuration → Administrative Templates → OneDrive

Policy Options: - Disable Files On-Demand: Prevents Files On-Demand entirely - Set maximum download bandwidth: Controls sync impact - Set sync location restrictions: Standardizes OneDrive paths

4. Testing Procedures

Test on representative systems: - One system from each hardware configuration - Different Windows versions (10 vs. 11) - Various OneDrive content sizes - Both personal and business OneDrive accounts - Document findings and create troubleshooting runbook

Monitoring and Maintenance

1. Backup Success Tracking

Monitor for OneDrive-related failures: - Configure alerts for error 0x029B0FFF - Track backup success rates by system type - Identify patterns (specific users, departments, configurations)

2. Disk Space Monitoring

For systems using Solution 1 (Files On-Demand disabled): - Monitor free disk space regularly - Alert when free space drops below threshold - Plan for storage upgrades proactively

PowerShell Monitoring Script:

3. OneDrive Sync Health

Regularly verify OneDrive sync status: - Check for sync errors in OneDrive settings - Ensure all files show green checkmarks (if Solution 1) - Monitor OneDrive sync logs for issues

4. Backup Content Audits

Periodically verify backup content: - Random sample restore tests - Verify OneDrive files present or excluded as expected - Confirm backup size aligns with configuration - Test restore procedures for both solutions

User Training

1. Education on Files On-Demand

Train users on: - What Files On-Demand is and how it works - How to identify online-only vs. local files - How to make specific files “always available offline” - Impact on backup and recovery

2. Self-Service Options

Empower users to: - Check their own OneDrive storage size - Adjust Files On-Demand settings (if permitted) - Request backup policy exceptions if needed - Understand what data is backed up vs. cloud-stored only

3. Best Practices

Educate on file management: - Store critical files in backed-up locations - Don’t rely solely on OneDrive for critical data - Understand recovery options for both Acronis and OneDrive - Know how to access OneDrive’s built-in version history

Alternative Backup Strategies

1. Microsoft 365 Backup

Consider Acronis Cyber Protect’s Microsoft 365 module: - Backs up OneDrive directly from Microsoft cloud - Bypasses local Files On-Demand issues entirely - Provides point-in-time recovery - Protects against ransomware and accidental deletion - Works alongside local system backups

Benefits: - No local disk space required - Works with Files On-Demand enabled - Covers all OneDrive content regardless of local status - Separate recovery path from local backups

2. Hybrid Approach

Combine strategies for comprehensive protection: - Local Acronis backup: System files, applications, settings (exclude OneDrive) - M365 Backup: OneDrive, SharePoint, Teams, Email - OneDrive versioning: Native Microsoft protection

3. Tiered Backup Strategy

Implement different approaches by user type: - Executives/Critical Users: Full local backup (Solution 1) - Standard Users: Exclude OneDrive (Solution 2) + M365 Backup - Remote/Mobile Users: Rely on OneDrive + selective local backup - Servers: Exclude OneDrive (rarely applicable)

Understanding OneDrive Files On-Demand

What is Files On-Demand?

Files On-Demand is a Microsoft OneDrive feature introduced in Windows 10 Fall Creators Update (version 1709) that:

Purpose: - Saves local disk space by not storing all files locally - Provides access to all OneDrive files through File Explorer - Downloads files on-demand when accessed - Maintains file metadata and thumbnails locally

Technical Implementation: - Creates NTFS reparse points (symbolic links) for online-only files - Reparse points contain metadata but not actual file content - Windows Shell extension intercepts file access requests - File content downloaded transparently when opened

File Status Types

OneDrive files can exist in several states:

Why Backup Applications Fail

Technical Reasons: 1. Reparse Points: Backup apps read reparse points, not actual file content 2. Read-Only Snapshots: VSS snapshots don’t trigger OneDrive download 3. API Limitations: Standard file I/O APIs don’t automatically hydrate files 4. Performance: Downloading files during snapshot would be too slow 5. Consistency: File state could change during backup operation

Making Files Always Available Offline

Users can selectively keep files local:

For Specific Files/Folders: 1. Right-click file or folder in File Explorer 2. Select Always keep on this device 3. File downloads and stays local permanently 4. File will be backed up by Acronis

Check Current Status: - ☁️ = Need to make available offline - ✅ = Already available offline

Comparison: Solution 1 vs. Solution 2

Decision Matrix

Choose Solution 1 if: - ✅ Disk space is not a constraint (>100GB free) - ✅ Complete local backup is required - ✅ Users work offline frequently - ✅ Fast file access is priority - ✅ Comprehensive disaster recovery needed

Choose Solution 2 if: - ✅ Disk space is limited (<50GB free) - ✅ OneDrive provides adequate protection - ✅ Users primarily work online - ✅ Faster backups preferred - ✅ OneDrive content is not mission-critical

Additional Resources

• Microsoft OneDrive Documentation:

  Files On-Demand Overview

• Acronis Knowledge Base:

  OneDrive Backup Compatibility

• Microsoft 365 Backup:

  Acronis Cyber Protect for Microsoft 365

Related Issues

• Error 0x029B0FFF during backup

• Error 0x0000FFF0 cloud operation not supported

• Reparse point backup failures

• OneDrive sync issues

• Files showing cloud icons in File Explorer

• Entire machine backup includes unwanted cloud files

Keywords

OneDrive backup fails, Files On-Demand, cannot back up cloud file, reparse point, symbolic link, OneDrive error, 0x029B0FFF, 0x0000FFF0, cloud operation not supported, online-only files, OneDrive sync, OneDrive exclusion, backup cloud files

Need Additional Help?

If these solutions don’t resolve the issue: 1. Verify OneDrive sync status in OneDrive settings 2. Check File Explorer - ensure files show expected icons 3. Review Acronis backup logs for specific file paths causing failures 4. Test with a single OneDrive file made available offline 5. Verify Windows version supports Files On-Demand (Win10 1709+) 6. Check for pending Windows or OneDrive updates 7. Contact Acronis Support with: - Screenshot of OneDrive settings - Backup error log - List of file paths failing to backup - Windows version information