How to Map File Server Folders to OneDrive Accounts

You want to make files on your company file server accessible through your OneDrive for Business accounts. The goal is to sync server folders so you can access them from any device without connecting to the corporate VPN. This article explains the two primary methods to achieve this: using OneDrive sync with SharePoint document libraries and using Windows Folder Redirection with Known Folder Move. You will learn the technical requirements, step-by-step setup instructions, and common pitfalls to avoid when mapping file server content to OneDrive.

Why Mapping File Server Folders to OneDrive Requires Migration

OneDrive for Business does not natively connect to on-premises file servers. The service is cloud-only and syncs files stored in Microsoft 365, specifically in OneDrive personal libraries and SharePoint document libraries. To make file server folders accessible via OneDrive, you must move or copy the data to a SharePoint site or use Windows Folder Redirection to change where user files are stored. Both approaches require careful planning to avoid data loss and permission issues.

The core technical constraint is that OneDrive sync client only communicates with SharePoint and OneDrive endpoints. It does not support SMB or NFS protocols. Therefore, any method you use must place the files inside a SharePoint document library or redirect local user folders to the cloud. This article covers the two most common and supported methods: uploading to SharePoint and syncing, and using Folder Redirection with Known Folder Move.

Method 1: Upload File Server Folders to SharePoint and Sync with OneDrive

This method moves your file server data into a SharePoint document library. Users then sync that library to their computers using the OneDrive sync client. This approach works best for shared departmental folders where multiple users need access.

1. Create a SharePoint site for the file server data
   Go to the Microsoft 365 admin center and create a new team site or communication site. Give it a name that matches the file server share, such as “Finance Files” or “Project Archive.”
2. Upload the file server folders to a document library
   Open the SharePoint site, navigate to Documents, and use the Upload button to copy the folder structure. For large amounts of data, use the SharePoint Migration Tool available in the Microsoft 365 admin center. This tool preserves permissions and metadata.
3. Set permissions on the SharePoint library
   Replace file server NTFS permissions with SharePoint permissions. Assign site members or visitors groups to control read and write access. Do not mix on-premises and cloud permissions on the same data.
4. Sync the SharePoint library to OneDrive
   On each user’s computer, open OneDrive settings, click the Account tab, and choose Add a account. Sign in with the user’s Microsoft 365 credentials. Then go to the SharePoint library in a browser, click Sync, and the OneDrive sync client will download the files to a local folder under the user’s profile.
5. Redirect mapped drive letters to the synced folder
   If users previously accessed the file server via a mapped drive, create a new drive mapping using the local path of the synced SharePoint library. For example, map Z: to C:\Users\[username]\SharePoint\Finance Files. Use a logon script or Group Policy Preferences to automate this mapping.

Method 2: Use Folder Redirection with Known Folder Move

This method redirects the user’s Desktop, Documents, and Pictures folders from the local computer or file server to OneDrive. It is best for personal user files that were previously stored on a file server home drive. Known Folder Move is a OneDrive feature that automatically moves these folders to OneDrive and keeps them synced.

1. Configure Folder Redirection Group Policy
   Open Group Policy Management Console. Create a new GPO or edit an existing one. Navigate to User Configuration > Policies > Windows Settings > Folder Redirection. Right-click each folder Desktop, Documents, Pictures and set the target to Redirect to the user’s OneDrive. Use the setting “Redirect the folder to the user’s OneDrive for Business account.”
2. Enable Known Folder Move in OneDrive
   In the same GPO, go to Computer Configuration > Administrative Templates > OneDrive. Enable the policy “Silently move Windows known folders to OneDrive.” This ensures that when users sign into OneDrive, their Desktop, Documents, and Pictures are moved automatically without prompts.
3. Migrate existing file server data to OneDrive
   Before applying the GPO, copy the contents of the user’s file server home drive to their OneDrive. Use the SharePoint Migration Tool or a manual copy. Ensure the folder structure matches what OneDrive expects: Desktop, Documents, Pictures at the root.
4. Apply the GPO and sign out or restart
   Link the GPO to the organizational unit containing the users. Instruct users to sign out of Windows and sign back in. When they launch OneDrive, the known folders will be redirected and synced to the cloud.
5. Remove the old file server home drive mapping
   After confirming that all files are synced, delete the user’s home drive share on the file server. Update logon scripts to stop mapping the old drive.

Common Issues When Mapping File Server Folders to OneDrive

OneDrive sync client shows error “This file can’t be synced”

This error occurs when the file server folder contained files or folder names that are invalid in SharePoint. Characters like #, %, and & are not allowed. Before uploading, rename files and folders to remove these characters. Use the SharePoint Migration Tool which automatically renames problematic items.

Folder Redirection fails because OneDrive is not configured

If Known Folder Move is enabled but OneDrive has not been set up on the user’s computer, the redirection will not work. Ensure that the OneDrive sync client is installed and that users sign in at least once before the GPO applies. You can deploy OneDrive via Microsoft Intune or Group Policy Software Installation.

Permissions are lost after migration

File server NTFS permissions do not transfer to SharePoint. You must reapply permissions using SharePoint groups. For Folder Redirection with Known Folder Move, the user’s personal OneDrive is private by default. No other user can see those files unless the owner shares them.

Upload to SharePoint vs Folder Redirection: Key Differences

Item	Upload to SharePoint and Sync	Folder Redirection with Known Folder Move
Best for	Shared departmental folders accessed by multiple users	Personal user files like Documents and Desktop
Permission model	SharePoint groups and site permissions	OneDrive personal library, private by default
Sync behavior	Users sync the library manually or via policy	Automatic sync via Known Folder Move
File path on computer	C:\Users\[user]\SharePoint\[Site Name]	C:\Users\[user]\OneDrive – [Tenant Name]\Documents
File server retirement	Requires manual cutover after migration	Home drive can be removed after GPO application

Mapping file server folders to OneDrive requires moving data to SharePoint or redirecting user folders to OneDrive. The method you choose depends on whether the data is shared or personal. After migration, users can access their files from any device without connecting to the corporate network. To verify everything is working, open OneDrive settings and check that the sync status shows green checkmarks on all files. For advanced control, use the OneDrive Group Policy templates to enforce sync settings and block specific file types from syncing.