How to Fix "USB Accessories Disabled" on Mac Safely

If your Mac shows "USB Accessories Disabled", "USB Devices Disabled", or a message saying that a connected device needs more power, start with the USB connection and power path instead of jumping straight to an SMC reset. Apple's current USB Devices Disabled guidance recommends reconnecting the device, trying another Mac port, bypassing a USB or Thunderbolt hub, and making sure a self-powered hub is connected to AC power.

Quick Answer

• First check: Safely disconnect and reconnect the accessory, then try another compatible port on the Mac.
• If a hub is involved: Connect the accessory directly to the Mac, or make sure a self-powered hub is plugged into its AC adapter.
• On Apple silicon: Do not use old Intel SMC key combinations. A restart, or a shutdown followed by power-on, resets the SMC automatically.
• If a drive works again but files are missing: Stop writing to the source drive and recover files to a different healthy drive.

Part 1. What "USB Accessories Disabled" Means on a Mac

Before trying fixes, identify which type of USB problem macOS is actually reporting. A power warning, an accessory-approval prompt, a dead USB port, and a storage device with missing files can look similar at first, but they require different actions.

The "USB Devices Disabled" warning is primarily about available USB power. Apple says drives, cameras, keyboards, hubs, and other connected devices can request a limited amount of power. When a device is not recognized and macOS says that it needs more power or that USB devices are disabled, troubleshoot the connection and power path first.

One important distinction is the "Allow accessory to connect?" prompt on a Mac laptop with Apple silicon. That is a security-authorization prompt, not the same power warning. Apple documents it separately in its accessory approval guidance for Apple silicon Mac laptops.

Part 2. Protect Your Data Before Disconnecting a USB Drive

If the affected accessory is an external SSD, hard drive, USB flash drive, memory-card reader, or camera, protect the data before repeated troubleshooting. The goal is to avoid turning a connection problem into a larger data-loss problem.

• If the drive is still mounted and a file transfer is stable, let the current operation finish, then eject the drive before unplugging it.
• If files have already disappeared, stop copying new data to the source device. New writes can overwrite recoverable data.
• Do not erase, initialize, or reformat a storage device just to clear a USB power warning.
• If the drive reconnects but files are corrupted or unreadable, use the dedicated corrupted or unreadable USB flash drive guide rather than treating file corruption as a USB-power issue.
• If a hard drive repeatedly disconnects, makes unusual mechanical noises, smells burnt, has liquid damage, or shows severe physical damage, stop powering it on and use a professional recovery service rather than repeated software scans.

Note: Data-protection steps matter most when the accessory contains irreplaceable files. Repair, erase, and formatting operations should come only after important data has been copied or recovered whenever that is still possible.

Part 3. How to Fix "USB Accessories Disabled" on Mac

Now that you have separated the power warning from data-loss and authorization problems, work through the fixes below in order. The first four follow Apple's warning-specific guidance; later steps are escalation options when the message keeps returning.

Step 1. Disconnect and Reconnect the Affected Accessory

Start by refreshing the physical connection without changing the disk itself. If the accessory is removable storage and is still mounted, eject it first. Then disconnect the accessory, wait a moment, and reconnect it securely. If several USB devices are attached, reconnect them one at a time so you can identify which connection causes the warning to return.

Step 2. Try Another Port on the Mac

The next check is whether the warning follows the accessory or stays with one port. Connect the same accessory to another compatible port on the Mac. If the warning disappears but one port remains unusable with multiple known-good accessories, the problem has moved beyond this warning-specific page and should be handled as a broader USB-port issue.

Step 3. Bypass the USB or Thunderbolt Hub

If changing ports does not help, simplify the connection path. When the accessory is connected through a USB hub, Thunderbolt hub, dock, display, or adapter chain, connect it directly to the Mac when possible. This removes a shared connection from the power path and is one of Apple's recommended checks for this warning.

Step 4. Power a Self-Powered Hub From AC

If you need to keep using a hub, verify how that hub receives power. A self-powered hub has its own external power adapter; make sure that adapter is connected and working. A powered hub can help when the shared connection does not provide enough power, but it will not repair a faulty accessory, cable, hub, or Mac port.

Step 5. Restart the Mac

If Apple's connection and power checks do not clear the warning, restart the Mac before trying controller-level steps. On a Mac with Apple silicon, Apple says no manual SMC key sequence is required: restarting, or shutting down and powering the Mac back on, resets the SMC automatically.

Step 6. Reset the SMC Only on an Intel-Based Mac If Needed

If the Mac is Intel-based and the warning persists after the earlier checks, an SMC reset can be considered as a later troubleshooting step. The SMC manages functions that include USB port power, but Apple also says that most users do not need to reset it. Confirm the Mac type and follow Apple's current SMC reset instructions rather than using an old one-size-fits-all key combination.

Intel Mac Laptop With the Apple T2 Security Chip:

1. Shut down the Mac.
2. Hold left Control, left Option (Alt), and right Shift for 7 seconds.
3. Keep holding those three keys and also hold the power button for another 7 seconds.
4. Release all keys, wait a few seconds, then press the power button to turn on the Mac.

Intel Mac Laptop Without Apple Silicon or a T2 Chip:

1. Shut down the Mac.
2. Hold left Shift, left Control, left Option (Alt), and the power button together for 10 seconds.
3. Release all keys, then press the power button to turn on the Mac.

Intel Desktop Mac: Shut down the Mac, unplug the power cord for 15 seconds, reconnect it, wait 5 seconds, and then turn the Mac on. Apple provides the same unplug-and-wait sequence for a desktop Mac with the T2 chip.

Step 7. Escalate If the Warning Still Returns

If the warning survives the power-path checks and the correct Mac-specific restart or SMC path, stop repeating the same resets. If one known-good accessory connected directly to the Mac still triggers the warning, or the message returns when no external accessory is connected, use Apple Support for hardware-level diagnosis. Avoid destructive disk actions or unverified Terminal commands just to suppress the message.

Part 4. Is It Actually "Allow Accessory to Connect"?

If the message on screen asks you to allow an accessory rather than saying USB devices are disabled, switch from power troubleshooting to accessory authorization. On a Mac laptop with Apple silicon, a new or unknown USB, Thunderbolt, or SD-card accessory can trigger an approval prompt. Apple says this is expected security behavior.

If you dismissed or denied the prompt, reconnect the accessory. You can also review the current setting by following Apple's USB and accessory connection guidance:

1. Choose the Apple menu and open System Settings.
2. Select Privacy & Security.
3. Scroll to Accessories.
4. Choose the appropriate "Allow accessories to connect" behavior. Apple lists "Ask for new accessories" as the default.

This setting does not solve a real "USB Devices Disabled" power warning. Use it only when macOS is asking for permission to connect the accessory.

Part 5. Recover Files After the USB Connection Works Again

Once the connection problem is resolved, check the storage state before doing anything destructive. Recoverit becomes relevant only if the external device is detectable but important files are deleted, formatted, missing, or inaccessible. If macOS detects the drive but Finder does not show it normally, use the dedicated external hard drive not showing up on Mac guide for that separate detection or mounting path.

For a detectable device with genuine data loss, the current Recoverit for Mac user guide follows a select, scan, preview, and recover workflow. The three steps below keep the recovery process focused on preserving the source device.

Step 1. Select the External Device

Connect the storage device directly and launch Recoverit for Mac. Choose the affected external device as the target location. If the source is specifically a USB flash drive, the USB flash drive recovery on Mac guide covers that recovery scenario in more detail.

Step 2. Scan the Removable Media

After selecting the source device, start the scan and use the available path, file-type, and search filters to narrow the results. Avoid copying new files to the source device while the scan is in progress because new writes can overwrite data that might still be recoverable.

Step 3. Preview and Recover to a Different Drive

When the scan returns results, preview the files you need, select the recoverable items, and click Recover. Save recovered files to a different healthy drive or location, not back to the source device, so the recovery process does not overwrite additional data.

No recovery software can guarantee that a file will be recoverable after its data has been overwritten. If the device repeatedly disconnects, makes unusual noises, overheats, or shows other signs of physical failure, stop scanning and use a professional recovery service.

Part 6. What Not to Do

When the warning involves a storage device, some common troubleshooting actions can create more risk than the original USB problem. Keep these actions out of the first-line workflow unless the connection is stable and important data is already protected.

• Do not format or erase the drive to fix a power warning: Formatting changes the storage device and is unrelated to Apple's first-line USB power fixes.
• Do not use old SMC shortcuts on Apple silicon: Apple says the SMC resets automatically when an Apple silicon Mac restarts or is shut down and powered on.
• Do not make Terminal or NVRAM resets your first move: Apple's warning-specific guidance starts with reconnecting, changing ports, simplifying the connection, and supplying AC power to a self-powered hub.
• Do not keep power-cycling a physically failing drive: Repeated attempts can worsen a hardware problem and reduce the chance of safe recovery.

Part 7. How to Prevent the Warning From Returning

After the Mac and accessory are working normally again, a few connection habits can reduce the chance of seeing the same power warning during future transfers or backup sessions.

• Give high-demand storage devices a direct Mac connection when practical.
• If several devices must share a hub, use the hub with its intended external power adapter when it is designed to be self-powered.
• Replace visibly damaged USB or Thunderbolt cables and avoid loose adapter chains.
• Eject external storage before unplugging it and keep a separate backup of irreplaceable files.
• If the same accessory repeatedly triggers the warning on different ports or computers, stop relying on it until the accessory and its cable or power supply can be checked.

Conclusion

When a Mac reports "USB Accessories Disabled" or "USB Devices Disabled," begin with the connection and power path: reconnect the accessory, change ports, bypass the hub, and supply AC power to a self-powered hub. Treat Apple silicon accessory approval as a separate security prompt, and reserve manual SMC resets for the appropriate Intel Mac cases. If the storage device becomes detectable but files are missing or inaccessible, protect the source from new writes before starting data recovery.