After migrating your files to OneDrive for Business, you may notice that the OneDrive sync client starts downloading every single file from the cloud to your local device. This behavior can fill your hard drive quickly and cause long sync times. The issue occurs because the sync client is configured to download files by default instead of keeping them as online-only placeholders. This article explains why this happens and provides clear steps to stop the mass download and switch to Files On-Demand.
Key Takeaways: Stop OneDrive from Downloading All Files After Migration
- OneDrive Settings > Sync and backup > Advanced settings > Files On-Demand: Turn on Files On-Demand to keep files as online-only placeholders instead of downloading them locally.
- Right-click OneDrive icon > Settings > Account > Choose folders: Select only the folders you need locally to prevent unnecessary downloads.
- Registry key HKCU\Software\Microsoft\OneDrive\Accounts\Business1\FilesOnDemandEnabled: Set to 1 to force Files On-Demand on if the toggle is missing or grayed out.
Why OneDrive Downloads Everything After Migration
When you migrate files to OneDrive for Business, the sync client may be configured to download all files because of a default setting or a group policy that disables Files On-Demand. Files On-Demand is a feature that lets you see all your files in File Explorer without downloading them. Files appear with a blue cloud icon and take up zero space on your local drive until you open them. After a migration, the sync client might treat the new OneDrive folder as a fresh sync and start pulling down every file. This can happen if the migration tool or IT policy sets the sync client to “Always keep on this device” for all items or if the Files On-Demand setting was turned off during the migration process.
Default Download Behavior in OneDrive Sync
The OneDrive sync client, by default, tries to download all files to ensure offline access. This behavior is controlled by the “Files On-Demand” setting. If this setting is disabled, every file you see in the OneDrive folder is actually downloaded to your device. After a migration, the sync client may not automatically re-enable Files On-Demand, especially if you are using a work or school account that has group policies applied. Additionally, if the migration process involved copying files from a local folder to OneDrive, the sync client may mark those files as “Always keep on this device” to preserve their local presence.
Group Policies That Force Download
In enterprise environments, IT administrators can set group policies that disable Files On-Demand. The policy “Prevent the use of OneDrive Files On-Demand” can be enforced via registry or Group Policy Object. When this policy is active, the sync client downloads all files to the local device. After migration, this policy will still be in effect, causing the mass download. You can check your registry at HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\OneDrive for the key FilesOnDemandEnabled. A value of 0 means the policy blocks Files On-Demand.
Steps to Stop OneDrive from Downloading Everything
Follow these steps in order to stop the mass download and enable Files On-Demand. You may need to pause sync first to prevent ongoing downloads while you make changes.
- Pause OneDrive Sync
Right-click the OneDrive cloud icon in the system tray. Select Pause syncing and choose 2 hours or 24 hours. This stops all upload and download activity temporarily. - Open OneDrive Settings
Right-click the OneDrive cloud icon again and select Settings. Go to the Sync and backup tab. - Enable Files On-Demand
Click Advanced settings. Under Files On-Demand, make sure the toggle is set to On. If the toggle is grayed out, see the registry fix in step 6. - Choose Which Folders to Sync Locally
Back in the Account tab, click Choose folders. Uncheck all folders that you do not need offline. Only keep the folders you access frequently. Click OK. OneDrive will remove local copies of unchecked folders but keep them online. - Make All Files Online-Only
Open File Explorer and navigate to your OneDrive folder. Select all files and folders inside. Right-click and choose Free up space. This changes all files to online-only icons. You can also right-click individual folders and select Clear local copies if the option is available. - Fix Registry if Files On-Demand Toggle Is Missing
Press Windows + R, type regedit, and press Enter. Navigate toHKEY_CURRENT_USER\Software\Microsoft\OneDrive\Accounts\Business1. Look for a DWORD value namedFilesOnDemandEnabled. If it does not exist, create it. Set the value to 1. Restart your computer and repeat steps 2 and 3. - Resume Sync
Right-click the OneDrive icon and select Resume syncing. OneDrive will now only download files when you open them.
If OneDrive Still Downloads Everything After the Fix
Group Policy Override Blocks Files On-Demand
If the Files On-Demand toggle remains grayed out and the registry value is set to 0, a group policy is blocking the feature. Contact your IT administrator to remove the policy. You can also check the registry at HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\OneDrive. If FilesOnDemandEnabled is set to 0, the policy is active. Administrators can change this value to 1 via Group Policy Management Console.
Files Stay as “Always Keep on This Device” After Migration
If individual files still show a green checkmark (always keep on this device) after using “Free up space,” the migration tool may have set file attributes that override the sync client. Right-click the OneDrive folder in File Explorer, go to Properties > General, and uncheck Read-only if it is selected. Then use the “Free up space” option again. If the problem persists, sign out of OneDrive and sign back in. Right-click the OneDrive icon, select Settings > Account > Unlink this PC. After unlinking, set up OneDrive again and immediately turn on Files On-Demand before any files sync.
Large Files Cause Download Even with Files On-Demand Enabled
Files On-Demand works for most file types, but some file types like PST files, ZIP archives over a certain size, or files with special characters may still download fully. This is a known limitation of the sync client. To avoid this, store large archives in a separate cloud-only location or use SharePoint document libraries for files that must remain online-only. You can also set individual folders to “Online-only” by right-clicking the folder and selecting Free up space.
Files On-Demand vs Always Keep on This Device: Key Differences
| Item | Files On-Demand | Always Keep on This Device |
|---|---|---|
| Default after migration | Often disabled | Often enabled for migrated files |
| Local disk space used | None for online-only files | Full file size for every file |
| File icon in File Explorer | Blue cloud | Green checkmark |
| Offline access | Requires manual download | Always available offline |
| How to set | Right-click > Free up space | Right-click > Always keep on this device |
After a migration, your OneDrive sync client may be set to download everything because Files On-Demand is off or because group policies force local storage. By enabling Files On-Demand and choosing only the folders you need offline, you can reclaim disk space and speed up sync. For persistent issues, check the registry for policy overrides or unlink and relink your account. As an advanced tip, use the OneDrive admin center to set Files On-Demand as the default for all users before migration to avoid this problem entirely.