Current Seagate hard drive products tested and supported in macOS 10.14 Mojave:
Backup Plus Family
Seagate Wireless Plus (with latest firmware)
Seagate Wireless (with latest firmware)
Seagate Personal Cloud
Seagate Internal Laptop and Desktop SATA hard drives
Seagate NAS Pro
Business Storage 4-Bay Rackmount NAS
Business Storage 8-Bay Rackmount NAS
If the Seagate hard drive is not being detected, try below USB External Troubleshooter steps:
Step 1: Try a different port.
Step 2: Try a different cable.
Step 3: Try a different computer.
Step 4: Verify the drive light is on.
Step 5: Try a different power outlet (Desktop Drives).
Step 6: Plug adapter directly into the wall if in a power strip (Desktop Drives).
Step 7: Verify that it the drive feels like it is getting power.
Step 8: For Windows, check Device Manager and Disk Management in computer management.
Step 9: For Macintosh, if the drive is not showing on your desktop or within Finder check disk utility (Applications > Utilities > Disk Utility).
Current Seagate software applications:
Paragon NTFS driver 15.4.x
Seagate Duet 1.4
If you are installing Seagate software applications for the first time, there is a security feature that was introduced in macOS 10.13 High Sierra and this feature has continued in macOS 10.14 Mojave. This feature requires user approval before allowing third-party kernel extensions (KEXT) to load. Follow below steps to enable Seagate software application extension in Security and Privacy of macOS:
Step 1: Perform Seagate software application installation. During the installation process a message will appear saying that a system extension tried to load.
Step 2: Click on Apple Icon > System Preferences > Security & Privacy.
Step 3: Click on Allow but if it that does not work then unlock the pane in the lower left-hand corner.
Seagate Knowledge: Will my Seagate drive work with macOS 10.14 (Mojave)?
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Seagate Knowledge: USB External Troubleshooter