latest Win10 boot medium wont boot

I checked the ESD folder - it was empty - so I deleted it

You said that you have created a version 1607 Windows 10 USB flash drive previously - that's still the current version that the Media Creation Tool will download (except for possibly 1 cumulative update which isn't the most current cumulative update anyway).

If you want to copy the current flash drive, use the Command Prompt (Admin) commands I provided to prepare the new flash drive to be bootable. Then copy the files and folders from the old flash drive to the new flash drive instead of downloading and mounting an ISO file.

NavyLCDR said:

You said that you have created a version 1607 Windows 10 USB flash drive previously - that's still the current version that the Media Creation Tool will download (except for possibly 1 cumulative update which isn't the most current cumulative update anyway).

If you want to copy the current flash drive, use the Command Prompt (Admin) commands I provided to prepare the new flash drive to be bootable. Then copy the files and folders from the old flash drive to the new flash drive instead of downloading and mounting an ISO file.

I do NOT want to copy it. I KNOW that v1703 either IS available or will be soon. I was hoping to install the bootstick and see what version the latest download was.

Sebastian42 said:

I do NOT want to copy it. I KNOW that v1703 either IS available or will be soon. I was hoping to install the bootstick and see what version the latest download was.

Version 1703 is not available via the media creation tool until at least April 5:
Managing Windows 10 Creators Update rollout for a seamless experience - - Windows 10 Forums

Also, you can right click on the .exe file for the Media Creation Tool and select properties, then details:



As long as it says product version 14393, it's going to create a version 1607 USB flash drive. The product version will change to 15063 when it is updated to create version 1703. Media Creation Tools will only download the version of Windows 10 that was available when the tool itself was downloaded. You have to download a new Media Creation Tool each time it is updated and a quick check is to look at the detailed properties of the mediacreationtool.exe file.

As long as the major build number (14393 current, 15063 likely for version 1703) is the same, you are always just 1 cumulative update away from being current.

Thank you for that very detailed information - I'm happy to wait till April 5 or later before having another attempt - at least now I know the criterion on which to base my judgement about the likely Winver. And I also know that I can clear away the earlier downloads. Is DiskCleaner the best way to get rid of the $Windows folders and the other associated folders ?

I prefer option two here :
Open and Use Disk Cleanup in Windows 10 - Windows 10 Performance Maintenance Tutorials