Symptoms
- Drive is detected and works fine on Computer A
- Same drive shows nothing or errors on Computer B
- Both computers are otherwise functioning normally
- Problem happens consistently, not randomly
Likely causes
- CommonComputer B's USB port isn't supplying enough powerOlder or lower-power ports, especially on some laptops, can't run certain external drives.
- CommonMissing or outdated USB/storage drivers on Computer BA fresh or outdated Windows install may lack a needed driver.
- PossibleFile system incompatibility, like a Mac-formatted drive on a Windows PC without extra softwareSome formats need additional drivers to read on a different OS.
- PossibleBIOS/UEFI settings on Computer B disabling certain USB or SATA modesLegacy vs. AHCI/USB settings can affect drive detection on some systems.
What to do
- Try the drive in multiple different ports on Computer B, including rear motherboard ports on a desktop.
- Check Device Manager on Computer B for warning icons related to USB controllers or storage.
- Confirm the drive's file system is one Computer B's operating system supports natively, or install the needed driver (e.g., for reading Mac-formatted drives on Windows).
- Update Computer B's chipset and USB drivers from the manufacturer's website.
- Check Computer B's BIOS/UEFI settings for anything related to USB or SATA mode that differs from Computer A.
- If Computer B genuinely can't detect any external drives at all, the issue may be with its hardware rather than this specific drive.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.