Sometimes, other programs—such as antivirus software or backup tools—can also cause this issue by interfering with the installation files, especially if there are leftover files or old recovery partitions from previous installations.
1. Check the WIMMount Path
A missing or incorrect path can block the upgrade process. To check the path, open the Registry Editor and navigate to: Double-click on it and make sure it points to the correct location for wimmount.sys. This file should be located in C:\Windows\System32\Drivers — before you make any changes, ensure the file really exists in that folder.
Once you’ve corrected the path, restart your PC and try the upgrade again.
2. If You’ve Used EaseUS Partition Master 10.5
This method is for people upgrading from Windows 8.1 and who have used EaseUS Partition Master 10.5. EaseUS may change your partition types, which causes issues with the upgrade. Here’s how your drive’s partitions should look:
Before using EaseUS for partitioning, the correct structure on a Windows 8.1 system should look like this:
After running EaseUS, the structure may change as shown below, and recagentc might fail to verify Windows RE.
In short, EaseUS changes your partition types. Here’s what you need to do to fix them, following the above diagram. Open Command Prompt as an administrator and enter these commands after confirming your partitions have changed:
select partition # Note: Select the Windows RE tools partition. set id=de94bba4-06d1-4d40-a16a-bfd50179d6ac select partition # Note: Select the 350 MB or 450 MB Windows RE tools partition (if you have this partition). set id=de94bba4-06d1-4d40-a16a-bfd50179d6ac select partition # Note: Select the Recovery image partition. set id=de94bba4-06d1-4d40-a16a-bfd50179d6ac list partition exit Next, run reagentc /info to check if things are fixed. If successful, it means your partitions are now set up correctly. You can now continue with your Windows 10 installation.
