1 – Turn off Hidden Files and Folders, and unprotect hidden operating system files.
Open Windows Explorer (Computer window), hit ALT key > Tools > Folder Options > View Tab > Radio button “Show hidden files, folders, and drives”, un-tick “Hide protected operating system files (Recommended)”
2 – Navigate to C:\Recovery. Add your local Administrator account to the Security tab.
Right click the folder, select Security tab, Click “Continue” button to view the object’s security properties, Add…, “Administrator” (you are editing an image that is in a workgroup from the built-in Administrator profile, aren’t you?), Grant “Full Control”, Apply, OK.
3 – Double click past the GUID folder. Replace the Winre.wim with your custom WinPE/RE environment customized to your needs. Make sure the file is called “Winre.wim”. Also make sure it is x86 vs. x64 depending on your OS version.
You can check a particular WIM file information with the following command from an Elevated Command Prompt:
dism /Get-WimInfo /WimFile:"C:\Path\To The\wimfile.wim" /Index:#
dism /Get-WimInfo /WimFile:"C:\Program Files\Windows AIK\Tools\PETools\x86\winpe.wim" /Index:1
4 – Remove the Administrator account from the C:\Recovery folder, resetting it back to it’s original permissions.
5 – At this point, you can reboot your machine, press F8, select “Repair Your Computer” and wait for it to start up.