Sounds strange that the USB is definitely broken…
Maybe a driver issue after some troubles within the target?
Can you try some basic steps?
- Give a try to start from a fresh boot (can help if you really have a driver issue), with everything unpluged on the device (power supply, USB cable)
- plug power & USB on the device
- Check in Windows Device Manager that the port is live
- start DS and check the port is available here
- try to connect
- As you played a bit with several ports on the target, the Development Mode may be locked to another port (preventing DS to switch the USB port to Development Mode); To fix this, try to send AT+WMD=0;+CFUN=1, wait for device reset is complete, and try to refresh target status.
- Another try may be to disable your Open AT app, in order to check if it causing troubles to the connection (can happen). --> AT+WOPEN=0
From there, we could go forward on the diagnostic…