Hi all I'm working on a STM32F303CC very simple board. I need to use a USB Virtual COM (CDC) for a MtoM data transfer with a Windows PC I set up BSP with STMCubeMx and compiling/debuging with Keil V5 with an STlink V2 in SWD mode board and microcontrolers are powered by USB all look's working great when I make a hard reset (just fresh power up) but if I try to make a soft reset like when entering in debug despite Virtual Com Port is well enumerated on windows side it could not open com port and no Usb transmit can be done on target side becase of Usb Device descriptor not defined in Usb Midle ware does anyone faced the same issue or somthing similare ? thank's for any help