Bios Recovery Acer Extensa 5235

Hello everyone,

wanted to flash a newer Bios version from the Acer Website. Flashed it via Windows. But the flashing went wrong.
I tried Crisis Recovery tool, followed the instructions and added the previous BIOS.wph to the USB-Stick.
I've used Fn+Esc, Fn+B, Win+B. But no matter what I try the laptop turns on and off endlessly (with black screen).
The stick-LED flashes but it won't read.
Tried a 4GB and 2GB stick (both with FAT32 & FAT16).

Has somebody ever solved the problem on the acer extensa 5235?

I only use this old Laptop because I've upgraded CPU and changed the HDD to a SSD. It worked like a charm. But now after the BIOS update it died.

Thanks for help!!