Some (beginners) problems with OpenSTM32
Hello,
Are you sure the STlink USB driver is installed correctly ?
You can reinstall it with the STLink usb driver installer from ST web.
http://www.st.com/content/st_com/en/products/development-tools/software-development-tools/stm32-software-development-tools/stm32-utilities/stsw-link009.html
Rgds,
Laurent