Step 8: For Windows, check Device Manager and Disk Management in computer management.
Step 7: Verify that it the drive feels like it is getting power.
Step 6: Plug adapter directly into the wall if in a power strip (Desktop Drives). Step 5: Try a different power outlet (Desktop Drives). If the Seagate hard drive is not being detected, try below USB External Troubleshooter steps: Seagate Internal Laptop and Desktop SATA hard drives Seagate Wireless Plus (with latest firmware)
Current Seagate hard drive products tested and supported in macOS 10.14 Mojave: