Data Protection Issues

Can Malware Delete OneDrive Synced Files? (How to Protect Data)

Maira Mehtab Sep 21, 2026 868 views

Question details

The user wants to know if local malware or ransomware can delete, encrypt, or modify files that are synchronized with OneDrive, and if those malicious changes will automatically sync to the cloud.

Product: Microsoft OneDrive
Device & OS: not provided
Scenario: Evaluating the security risks of keeping cloud storage folders synced to a local device that might become infected with malware.
Observed behavior: If malware runs with sufficient local permissions, it can access, modify, or delete the synchronized OneDrive files in File Explorer, and those changes will subsequently synchronize to the cloud storage.

Before you start

If you suspect your computer is currently infected with malware, immediately disconnect from the internet or pause OneDrive synchronization to prevent malicious changes from overwriting your cloud data.

Solution 1Recommended

Implement Essential Malware Prevention Practices

Since malware with local access can alter synced files, preventing the infection at the system level is the most effective way to secure your OneDrive data.

Because OneDrive is an automatic synchronization tool rather than a disconnected backup solution, any local file deletion or encryption caused by malware will be mirrored in the cloud. Protecting the local environment is critical.

Keep systems and applications updated

Regularly install the latest security patches for your Windows operating system, OneDrive client, and web browsers to close known vulnerabilities that malware exploits.

Use active antivirus protection

Ensure Windows Defender or a reputable third-party antimalware software is running in real-time, and schedule periodic full-system scans.

Operate with least-privilege accounts

Use a standard user account rather than an Administrator account for your daily computing tasks. This restricts malware from gaining the elevated permissions needed to encrypt or permanently delete critical files.

Practice safe browsing habits

Avoid downloading attachments from unknown email senders and do not click on untrusted links, which are the primary delivery methods for ransomware.

Synchronization vs. Backup: Remember that cloud synchronization is not a substitute for a true backup. Always maintain an independent, offline backup of your most important data.

Solution 2

Recovering Altered or Deleted Files in OneDrive

If malware has already deleted or encrypted your locally synced files, you can use OneDrive's built-in cloud recovery features to restore your original data.

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Enhance Your Document Security with WPS Office

While OneDrive and Microsoft Office handle synchronization, having a reliable and secure office suite is essential for managing your recovered files. WPS Office provides a lightweight, highly compatible alternative with built-in cloud protection and document encryption.

1. Download and Install WPS Office: Visit the official WPS website and download the free installation package for your operating system.
2. Set up WPS Cloud: Create a free account to activate WPS Cloud, enabling auto-save, secure document synchronization, and version history.
3. Open and edit your recovered files: Easily open the documents you restored from OneDrive directly in WPS Office without worrying about formatting loss.

Fully compatible with Microsoft Office file formats, including .docx, .xlsx, and .pptx.Built-in document encryption and password protection to safeguard against unauthorized access.Integrated WPS Cloud offering secure storage and file version history to easily recover previous document states.Lightweight application that consumes fewer system resources, ensuring fast performance even during system scans.

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Frequently Asked Questions

Can ransomware encrypt my OneDrive cloud files?

Yes. If your OneDrive account is synced locally to a computer that becomes infected with ransomware, the malware can encrypt the local copies of the files. The OneDrive client will then sync these encrypted versions to the cloud, replacing the clean files.

Is OneDrive synchronization considered a full data backup?

No. Synchronization simply mirrors the state of your local folders to the cloud. If a file is accidentally deleted, corrupted, or removed by malware locally, that deletion is synced. A true backup creates independent, historical copies of your data that are isolated from local changes.

How far back does OneDrive version history go?

For personal Microsoft accounts, OneDrive typically stores file versions for up to 30 days. For work or school accounts, version history retention policies are configured by the organization's IT administrator.

Will formatting my PC delete my OneDrive cloud files?

Formatting your PC unlinks and erases the local storage, but it does not delete the files stored securely in your OneDrive cloud account. Once you reinstall your operating system and sign back into OneDrive, your files will be available to download again.

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