Why are some OneDrive files showing as 0KB or appearing corrupted, and how can I prevent this from happening again?

Question

Hello,

I recently worked with a user who noticed that several files in their OneDrive appeared as 0KB or showed up as corrupted. We tried the usual troubleshooting steps—signing out and back in, checking both the regular Recycle Bin and the Second-Stage Recycle Bin, etc.

At the moment, the user has recovered the specific files they needed (class presentations downloaded from Canvas), and they mentioned they can locate their PDF books elsewhere even though the OneDrive versions show as 0KB. So they’re not missing anything critical right now.

The concern is why this happened in the first place and whether it could happen again. The user is worried that other files or folders they haven’t accessed yet might also be affected. They’ve even started backing up their OneDrive files to Google Drive as a precaution.

Before escalating this to Microsoft support, I wanted to ask the community:

Has anyone seen OneDrive files randomly becoming 0KB or corrupted? What typically causes this, and is there anything we can do to prevent it from happening again?

Any insights or similar experiences would be really helpful.

Thanks,

Answer 1

Hi @Zhwakk Ahmadzai,

Thank you for reaching out. 

Regarding your concerns, I’d like to clarify that the answer is yes. In most cases, files showing as 0 KB or corrupted in OneDrive are caused by a sync issue (such as an incomplete upload/download, Files On‑Demand placeholder not hydrating, or a local cache/state problem) rather than OneDrive randomly corrupting cloud data. 

Here are a few safe checks and preventative steps you can use:

1/ You can check if it’s local-only or truly in the cloud.

• Try opening/downloading the same file from OneDrive on the web. If the web copy is healthy, the issue is typically on the device (sync cache / Files On‑Demand) rather than the service.  

2/ Check OneDrive sync health and sync problems 

• The OneDrive tray icon/status and File Explorer sync icons can indicate whether sync is paused, stuck, or needs attention. If the client is not fully syncing, online-only items may appear but fail to open properly.

3/ Reset the OneDrive sync app 

• Microsoft documents that resetting OneDrive can resolve sync issues and triggers a full resync of content/state. 
  • You can refer to this article to reset OneDrive: Reset OneDrive - Microsoft Support 
• After a reset, your user may need to reselect any “choose folders” settings they previously configured. 

4/ Consider the impact of Files On‑Demand and potential interactions with third‑party security or encryption software.

• Files On‑Demand uses placeholder files and downloads content only when accessed. If the client is unable to properly hydrate a file, it may appear unavailable or unusable on the local device.
• In some cases, third‑party security or encryption tools may interfere with Files On‑Demand placeholders. For example, certain encryption solutions have been observed to cause symptoms similar to local file corruption. If a security agent is in use, testing Files On‑Demand behavior or setting critical folders to Always keep on this device may help reduce the risk to important data.

Note: for important folders (school/work documents), consider marking them as Always keep on this device so they are fully downloaded and less dependent on on-demand hydration.   Encourage users to verify the client shows “synced” after large copy/move operations and to review any reported sync problems promptly.  

Hopefully, these steps provide the user with more confidence in their data integrity.

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