Why does my Mac not recognize USB devices?

I had issues with my Mac not recognizing USB devices, and I realized that security software sometimes blocks external devices. If you have any antivirus or endpoint protection software installed, try temporarily disabling it to see if the USB device is recognized. Here are the steps:
1. Open your security software.
2. Look for options related to external devices or ports.
3. Disable these settings temporarily.
If this resolves the issue, you’ll need to adjust the software settings or contact the software provider for more permanent solutions.

I once faced a similar issue, and the solution was surprisingly simple. Sometimes, macOS might have disabled the USB ports due to an error or power surge. Here’s a quick check:
1. Open the ‘System Information’ application (hold the Option key and click on the Apple menu, then select ‘System Information’).
2. In the System Information window, under ‘Hardware,’ click on ‘USB.’
3. Look for your USB device in the list.
4. If it’s not there, either restart your Mac in Safe Mode (holding down the Shift key during startup) or try resetting the NVRAM/PRAM (restart and hold Option + Command + P + R for about 20 seconds).
These steps can often re-enable the USB ports and allow the device to be recognized again.

I’ve had a similar issue and discovered it could be due to the macOS needing an update. Sometimes, when the operating system is outdated, it might not be compatible with certain USB devices. Here’s what you can do:
1. Click on the Apple menu in the top-left corner of your screen.
2. Select ‘System Preferences,’ then click ‘Software Update.’
3. Install any available updates.
4. Restart your Mac and then reconnect your USB device.

I’ve found that sometimes the problem is related to my user profile settings. Creating a new user account temporarily can help determine if that’s the issue. Here’s how to set up a new user account:
1. Go to ‘System Preferences,’ then select ‘Users & Groups.’
2. Click the lock icon and enter your administrator password.
3. Click the plus (+) button to add a new user.
4. Set up the new account with standard settings and log in.
Connect your USB device with the new user account and see if it’s recognized. If it works, there might be a software conflict or a setting issue in your original user profile.

When my Mac wouldn’t recognize my USB devices, I discovered it was actually a problem with the System Management Controller (SMC). Resetting the SMC often resolves hardware-related issues like this. Here’s how you can do it:
1. Shut down your Mac completely.
2. Press and hold the power button for 10 seconds.
3. Release the power button, then wait a few seconds.
4. Press the power button again to turn on your Mac.
This process resets the SMC on most Mac models. You should then reconnect your USB device to see if it’s recognized.

I’ve encountered the same problem, and I found that sometimes the USB ports themselves can get dirty or damaged. Here’s a quick tip: Use a can of compressed air to blow out any dust or debris from the USB port. Gently clean the port, then try connecting your USB device again. This simple step has helped me on more than one occasion.

A colleague of mine suggested checking if the USB device is formatted in a file system that macOS supports. Macs generally support FAT32, exFAT, and HFS+, among others. If the USB drive is formatted in an unsupported file system (like NTFS without any additional drivers), it won’t be recognized. Here’s what you can do:
1. Connect the USB device to a Windows PC.
2. Check the file system format.
3. If it’s not macOS-compatible, back up the data and then reformat the USB drive to exFAT using the Disk Utility on your Mac.

In my experience, the problem often lies in the USB device itself. It might not be getting enough power from the Mac. You could try using a powered USB hub. This can sometimes resolve the issue because it ensures that the USB device gets sufficient power to function properly.