Arduino for STM32

I'm using the official stm32 core v1.9.0 I have already been through all those but nothing there to help me with my problem. Am I best to comment there rather than on here? I'm using Arduino 1.8.12 with windows 10. After flashing the low-medium density binaries for pc-13 the blue pill will show up a...

I'm getting the error described below which does not indicate much info, here is the video guide I followed. I have tried this on 5 different blue pills, some of which are 128k they are all different models from different batches/suppliers. I uploaded the stm32 binaries via st-link 32. https://www.y...