When one of the drives doesn't appear in File Explorer, you can try these troubleshooting steps on Windows 11 to resolve the issue.

If the hard drive is missing in File Explorer, you can quickly troubleshoot and fix this problem with Disk Management, Device Manager, DiskPart, and other tools, and here’s how on Windows 10.

The SSD not showing up on Windows 11/10 File Explorer but appearing in Disk Management could be because of a corrupted or incompatible file system. Thus, you can format the disk.

After rebooting both drives disappeared. They loaded up during boot up, they show up as drives in Explorer and Power Desk. They do not work and do not appear in Systems, Device manager.