Hi and Welcome!
that’s bad. Do you remember the error message?
The only idea I have is to flash under plain DOS. Please check the firmware chapter of the FAQ (see my signature) and also the “[B]Read First[/B]: Howto flash…” thread.
It is recommended to create a bootable USB memory device for that job.
I don’t have personal experience with the DOS flashing procedure, so I can’t provide much more help here.