Help! Need desperately help.

[waldmattis]

Good evening.
I'm sitting with a friend to finally flash the eMMC memory of his Tinker Board S.
This under Linux MX-18, 64bit, Etcher as brand new AppImage.

Etcher found the eMMC memory and apparently started flashing, but finished the process after about 1 second.
I took 4 screenshots, which I enclose as an attachment.

Then I tried it under Windows 7, 64bit.
When connecting the Tinker Board S to a USB port, Tinker was detected,
but Windows required formatting of the emmC memory, which I allowed.

After a quick formatting eMMC was recognized as a removable drive.

Etcher (Windows) recognized the flash memory, but aborted the
flash process after one second like Etcher under Linux.

Then I completely formatted the flash memory under Windows, i.e. overwriting it.
Now eMMC is neither recognized under Linux nor under Windows.

Windows tries to install a driver, but aborts it with the message "unknown device".

Have I possibly destroyed the eMMC by overwriting the formatting?

Who can help?

Thank you for every hint.
It greets you
Karl

[Im4Tinker]

You should read this and maybe my writeup on the third page.