Ok, This message
talk about an issue which have been solved by formatting the floppy on the asr-x first. (in french)
The error message isn't really the same, it displays "bad checksum" (usually, it means the device don't count the same amount of data as it expect. The sum of the bytes is usually written, or calculated in the OS file. The program compare it at the end, or the beginning of the update process )
EDIT : I don't know how he could did it, if his asr was bricked.
-> His ASR wasn't bricked, just the new floppies didn't worked
The interesting point is he said no floppy worked as long as the formatting hadn't been done by the ASR-x itself.
Now you are sure your floppy drive is ok, you must try to make new os floppies. Do you have you to an old PC (win 98,2000 or Ms-dos) ? Can you check by yourself what was written on your floppies ?