1. You installed Bootable Media Builder and appropriate Windows AIK/ADK for creating WinPE media.
2. WinPE media creation fails with the following error:
The user attempted to mount to a directory that is not empty. This is not supported.
Folder C:\Users\%username%\AppData\Local\Temp\~MntWIM that is used to store temporary mounted .wim image is not empty.
Delete or rename C:\Users\%username%\AppData\Local\Temp\~MntWIM folder, then reattempt WinPE media creation.