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What Is the Usbd Process? Restart It to Fix iPhone Connection Issue!

Updated on Tuesday, December 3, 2024

iBoysoft author Amanda Wong

Written by

Amanda Wong
Professional tech editor

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Jessica Shee

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Summary: This is a complete introduction to the macOS usbd process, it tells what the usbd is, what the role it plays, and how to fix usbd-related issues such as the iPhone keeping connecting and disconnecting from the Mac.

macos usbd process

The issue is that some Macs and iPhones don't have a stable connection when connected via the Apple USB Lighting cable. The iPhone often attempts to reconnect very quickly, sometimes reconnecting 2-3 times per a second and continues to do this in an endless loop. Sometimes it will stop if you wiggle the USB Lighting cable, insert it into another USB port or pause the particular Mac process usbd in Terminal.

For years, Mac users have reported iPhone connection issues on Mac devices, and killing the macOS usbd process is an effective solution to fix iPhone keeps connecting and disconnecting. In this post, we are going to dive into this system daemon to help you understand the usbd process.

What is the macOS usbd process?

The usbd(stands for USB daemon) process on macOS is a system daemon that is responsible for managing and handling USB device interactions and communication on the system. It is a crucial part of macOS's USB framework, as it works in the background to ensure that connected USB devices (such as keyboards, mice, external drives, etc.) are recognized and can function correctly with the operating system.

How does usbd work on Mac?

When you plug a USB device into your Mac, usbd helps the system detect the device, load necessary drivers, and establish the connection. Without it, your Mac wouldn't be able to interact with USB peripherals, as this process is fundamental for the operating system to recognize and manage external hardware.

usbd works in conjunction with other macOS subsystems, such as the IOKit framework, which provides the underlying infrastructure for hardware drivers, and the IOUSBFamily driver, which is a part of macOS's USB driver stack. In addition, user-facing software like Disk Utility or System Preferences/Settings may rely on usbd to interact with USB storage devices or settings.

How to troubleshoot usbd issues?

If you encounter problems with USB devices such as USB flash drive not showing up on MacUSB devices keeping disconnecting, USB devices not being recognized, or freezing, the usbd process might be involved. Common troubleshooting steps might include:

  • Fix 1. Check USB devices: Ensure that the USB devices themselves are not faulty. Try connecting them to another computer to confirm they're working.
  • Fix 2. Kill the usbd process: Open Terminal and run the command [sudo killall -STOP -c usbd] to pause the process, if the issue remains, try command [sudo killall -CONT -c usbd] to restart the usbd process, quit a lot of Mac users find this solution helpful.kill usbd process
  • Fix 3. Restart your Mac: A simple restart often resolves temporary glitches with system processes like usbd.
  • Fix 4. Reset the SMC and NVRAM:  These resets can help if your Mac is having trouble with hardware recognition, including USB devices.
  • Fix 5. Update macOS: Make sure your Mac is running the latest macOS version, as updates can fix bugs or compatibility issues with USB devices.

Spread this informative post about the macOS USB process!