Try to download the driver using this keyword:samsung hd400ld usb device driver in google search.
Reasons why the external hard drive not showing up Windows 10, 8, 7
When you use an external hard drive such as Samsung in different computers with a previous OS and it was previously working, a problem or issue may arise when Windows 10 not detect it or it is not showing up.
There is a possibility that something wrong with the driver software, it could be broken or outdated and you to update it by downloading the new driver software online.
Quick Fix
- Check the USB port, cable, and the connection if it is working properly
- Check if your external hard drive can be recognized or detected in Disk Management
- Troubleshoot the computer or laptop
- Update the driver, check for software updates
If you can't fix the error, try to use the third-party data recovery tool to get back the data first.
Source: Quick Fix for External Hard Drive not Showing up on Windows 10
