When the Windows 10 upgrade stops during the Safe-OS phase / Migrate-Data process, it usually means that Windows hit a problem while moving user profiles, drivers, or system settings. This is a fairly common upgrade error.
Here are some things you can try to fix it:
- Disconnect External Devices
Unplug all non-essential USB devices (printers, external HDDs, webcams, etc.). Sometimes drivers for these interfere with migration.
- Check for Problematic Software
Remove or update antivirus/security software (e.g., McAfee, Norton, Kaspersky).
Uninstall older programs that may not be compatible with Windows 10.
- Run
appwiz.cpland check for outdated drivers/utilities.
- Run Windows Update on 8.1 First
Make sure Windows 8.1 is fully updated before upgrading:
Open Windows Update and install all important updates.
- Restart and recheck until no updates remain.
- Update Drivers (especially Storage/Chipset)
Update your chipset, storage (SATA/RAID), and graphics drivers from your PC manufacturer’s site.
- Old drivers are one of the biggest causes of migration failure.
- Check Disk Health
Corrupt files or bad sectors can break the migration:
sfc /scannow
chkdsk C: /f /r
Run both from an elevated Command Prompt.
- Free Up Space
Ensure at least 25–30 GB free on the system drive.
- Try the Upgrade via Media Creation Tool
Instead of relying on Windows Update:
Download the Media Creation Tool from Microsoft.
Choose Upgrade this PC now.
- This method is more reliable than the auto-update.
- Check Setup Logs (for exact error)
If it still fails, the logs can tell what blocked the migration:
- After rollback, check:
C:\$WINDOWS.~BT\Sources\Panther\setuperr.log
C:\$WINDOWS.~BT\Sources\Rollback\setupact.log
Search for error codes like 0xC1900101, 0x20004, etc.