📘 Knowledge Base

Migrating Mapped Network Drives to OneDrive for Business (Per User)

🎯 Overview

Legacy mapped network drives (e.g., H:\, U:\, \\fileserver\users\%username%) are commonly used for user file storage. Microsoft recommends replacing these with OneDrive for Business for individual user data and SharePoint Online for shared/team data.

This guide walks through planning, preparing, migrating, and validating the transition.

🧭 Migration Strategy

What Goes Where

👉 Key rule:
If the data belongs to one person → OneDrive
If it’s shared → SharePoint

🧱 Phase 1: Assessment & Planning

1. Inventory Mapped Drives

• Identify all mapped drives (logon scripts, GPOs, Intune)
• Document:
  • UNC paths (\\server\home\user1)
  • Size per user
  • Permissions (NTFS + share)

2. Identify User Home Drives

Typical structure:

\\fileserver\home\%username%

✔ These map directly to:

User OneDrive → /Documents/

3. Clean Up Data (Critical)

Before migrating:

• Remove duplicates
• Archive old files
• Remove unsupported file types

✔ This reduces migration time and storage costs

4. Validate OneDrive Readiness

Ensure:

• Users have Microsoft 365 licenses
• OneDrive is provisioned (can take up to 24 hours)
• Known Folder Move (optional) planned

⚙️ Phase 2: Prepare Environment

1. Pre-Provision OneDrive

Run PowerShell (example):

Request-SPOPersonalSite -UserEmails user@company.com

✔ Required before migration tools can target user drives

2. Configure OneDrive Policies

Recommended:

• Enable OneDrive Sync Client
• Configure Known Folder Move (Desktop/Documents/Pictures)
• Set storage quotas
• Enable MFA

3. Select Migration Tool

Microsoft Native Option (Recommended)

• Migration Manager (Microsoft 365 Admin Center)
  ✔ Centralized
  ✔ Agent-based
  ✔ Load-balanced migrations

Alternative tools:

• SharePoint Migration Tool (SPMT)
• Third-party (Cloudiway, BitTitan, Quest)

🚀 Phase 3: Migration Execution

Option A: Migration Manager (Recommended)

Step 1: Install Migration Agent

• Install on file server
• Connect to Microsoft 365

Step 2: Create Migration Tasks

Map:

Source: \\fileserver\home\user1
Destination: OneDrive → user1@domain.com

Step 3: User Mapping

Critical requirement:

• Source user → Target M365 user

✔ Incorrect mapping causes permission/data issues

Step 4: Run Scan (Pre-check)

Detect:

• Long paths
• Invalid file types
• Permissions issues

Step 5: Run Initial Migration

• Runs in background
• No user disruption

Step 6: Delta Sync

• Captures changes made during migration
• Ensures no data loss

✔ Recommended for large environments

Step 7: Cutover

• Disable mapped drives (GPO/logon scripts)
• Redirect users to OneDrive

👥 Phase 4: User Transition

1. Communicate to Users

Include:

• Migration timeline
• New file location (OneDrive)
• How to access files

✔ Communication is critical to adoption

2. Train Users

Cover:

• OneDrive access (web + sync client)
• Sharing files
• Version history
• File recovery

3. Deploy OneDrive Sync

Users will see:

C:\Users\%username%\OneDrive - CompanyName\

🔐 Permissions Considerations

• NTFS permissions → mapped to OneDrive permissions
• Most restrictive permission wins
• Advanced NTFS permissions may be removed

⚠️ Expect:

• Some permissions must be manually revalidated

✅ Phase 5: Validation

Perform Post-Migration Checks:

• File count matches
• Folder structure intact
• Permissions validated
• Users can access files

✔ Always run pilot migrations first (5–10 users)

🧪 Pilot Migration (Highly Recommended)

Before full rollout:

• Select test users
• Migrate data
• Gather feedback
• Adjust process

✔ Prevents large-scale failures

🧯 Common Issues & Fixes

🔄 Automation (Optional)

You can automate:

• User mapping via CSV
• Bulk migrations
• PowerShell provisioning

🧠 Best Practices Summary

• ✔ Clean data before migration
• ✔ Run pilot first
• ✔ Use delta sync
• ✔ Communicate early and often
• ✔ Separate personal vs shared data
• ✔ Validate permissions post-migration

📌 Final Architecture (After Migration)