This article applies to:
D1 and D1 Pro with all laser modules
When the machine's firmware is wrong (e.g. D1 using D1 Pro's firmware), it will cause the USB connection to fail, and result in the shaft being locked.
Check the Force firmware
Use the firmware tool to force a firmware update.
After updating the firmware, restart the machine to test if it can connect.
If the problem persists, contact tech support and get a new motherboard.
If None of the Above Works
If you have followed the instructions above and the issue is still not resolved, please read the article in the link below, collect the troubleshooting steps you have taken, and contact xTool tech support for further advice.