if anyone get mesage "no bootcore detected" there is simple solution
You must use nonoriginal siemens cable without autoignition
and check the checkbox -> precheck---- SKIP
before press start make concentrate of water and salt and paste a little drop in cuted slot(skratch) , but little...
pres start and winswup will BOOT your phone , but whatt of this
... if phone swiching on normal winswup and original cable work too,
but when phone not swiching on or swichoff itself quickly with this metod you can flash it , and probably nothig goes better , at least you can try