Q. So I was doing a clean install of Windows 10 using a USB and I deleted all the partitions including the system reserve one. The only drive left now is “Drive 0 Partition 1”. It is set as primary. 
The problem is everything I click to continue the installation, I get the error “They couldn’t create a new partition or locate an existing one.”

Answer.

Try this out:

Solved: Setup was unable to create a new system partition or locate an existing system partition