Mac Doesn’t Detect Your USB Drive? Here’s the Fix

Plugged in a USB drive and your Mac doesn’t seem to notice it? Whether you’re using an external flash drive, hard disk, or SSD — this issue can usually be resolved with a few quick checks and tools already on your system.

🧰 Step 1: Use Terminal to Check System Detection

🖥️ Step 1: Open the Terminal App

Press Command (⌘) + Space to launch Spotlight Search.
Type Terminal, then press Enter to launch it.

2. Enter this command in Terminal

Copy the following command and paste it into Terminal, then press Return:

Click "Show Command" to reveal

This command shows all drives connected to your Mac. If your USB drive appears in the list, it’s detected but might not be mounted or formatted correctly.

📂 Step 2: Open Disk Utility

Go to Applications → Utilities → Disk Utility. Look for your USB drive in the sidebar. If it’s there but grayed out, select it and click Mount.

🧹 Step 3: Run First Aid

In Disk Utility, select the USB drive and click First Aid to repair possible file system issues. This can often make the drive usable again.

🔌 Step 4: Try a Different Port or Adapter

Sometimes it’s not the drive — it’s the port. Try connecting your USB device to another USB port or use a different adapter if you’re on a Mac with USB-C only.

🔄 Step 5: Restart Your Mac

A simple restart can reset hardware detection systems and resolve temporary connection glitches.

📦 Step 6: Reformat (If Needed)

If the drive shows up but cannot be opened, you may need to reformat it. Be aware: this will erase all data on the drive. Use Disk Utility and choose a format like ExFAT for cross-platform compatibility.

Note: If your drive still isn’t showing up after these steps, test it on another computer. If it fails there too, the drive itself may be damaged.