Bootcamp issue: The startup disk cannot be partitioned or restored to a single partition I tried installing windows 10 on mac but some sort of error occured and since then boot camp had been removing the partitions for hours. So I ran "diskutil eraseVolume fat32 BOOTCAMP disk0s3" on terminal as mentioned on another thread: Stuck on "please wait while Boot Camp Assistant is removing the partitions it created". Then I closed the Bootcamp window and reopened. Now that I click "Continue" on the Introduction, it prompts: "The startup disk cannot be partitioned or restored to a single partition. The startup disk must be formatted as a single Mac OS Extended (Journaled) volume or already partitioned by Boot Camp Assistant for installing Windows."

I no more want to install Windows. Please help me restore the storage used up for windows.

Thanks in advance.

(Running macOS Mojave(10.14.1) on Macbook Air(2017))
I had the same issue. I solved it with following steps:


Stop Bootcamp Assistant 
Eject all external drives (USB sticks and
mounted ISO files) 
Restart Mac 
Relaunch Bootcamp Assistant  


Normally you will be able to follow restore the previous state without Bootcamp partition.

By the way in my case the origin of the problem was probably the use of a MSDN ISO of Windows 10 including multiple installs.

I downloaded an ISO from https://www.microsoft.com/fr-fr/software-download/windows10ISO and could complete the Bootcamp Assistant.