
- Way 1: Boot Mac from USB Drive using Startup Manager. Getting your Mac to load from a USB drive is fairly straightforward. Use the following steps, you can easily set Mac boot from an external drive in Startup Manager, so it'll only boot from USB that one time. Step 1: Insert the USB boot media into a USB slot.
- MacBook USB ports not working, reading? Try an SMC + PRAM Reset to solve this problem. MacBook USB port not working properly? Or won't recognize any USB devices? Seems like there is a bunch of people who are having USB ports issues in MacBook Pro or Air. Don't worry anymore, Here is a way to solve this issue.
- I checked with another working usb-c cable and another charger and it didn't charge. I tried the 10sec reset and nothing. Tried SMC reset and nothing. None of the USB C ports ate charging. But they seem to work since I plugged in a dingle/hub with a fan, a mouse and an ssd drive and it works.
I can no longer can use any USB-A devices like my DJ controller and bike trainer when connected to any of my systems USB-C ports with either a dongle or a direct cable USB-C to USB-B. I have done all the usual stuff SMC reset NVRAM/PRAM and nothing has fixed it. Drives work fine, HDMI plugged. MacBook Pro 15' Touch Bar Late 2016. Apple's line of laptops for professional and power users. To date the MacBook Pro line includes 13, 15, 16, and 17-inch variants, with major revisions defined by unibody, Retina display, and Touch Bar designs.
Troubleshooting the device:
1. Make sure connection to the USB port is secure
Unplug the affected device from the USB port and then plug it back in. Make sure that the connection is secure.
2. Unplugging other devices that's plugged into the USB ports
For troubleshooting purposes, unplug all USB accessories from the computer. Then start plugging in USB devices one at a time, testing each one to make sure they all work before adding the next. Sometimes two devices will have a conflict and won't work together. If you find this to be the case, contact the manufacturer for assistance.
3. Is it a new device, or a device that stopped working?
Ask yourself, is this a new device that never worked, or is it a device that you've had for a while that suddenly stopped working? If it used to work, think about what changed just before the device stopped working. Did you recently add another new device? Install a new program? Try reverting the computer to the way it was before the device stopped working. If it works again, there is an incompatibility with the device and whatever you added.
4. Check in the System Profiler
Open System Profiler from the Utilities folder, which is inside the Applications folder. From the Contents column on the left, under the Hardware header, select USB; the panel to the right will show all the USB devices that the computer recognizes. It may not identify them correctly by name, but it should have the right number of devices listed.
- If the device shows up in System Profiler, even if the device doesn't work, the issue is usually due to software. Your best solution is to try updating the drivers, creating a new user, or reinstalling the system software.
- If the device doesn't show up in System Profiler, the issue is more likely to be hardware—either the device or the USB port isn't working properly. In this event, continue on to the next item on this list. With each of the following items, check the System Profiler window (press Command-R to refresh the list) to see if the device appears.
5. USB port lacks power
If you have the device plugged into a USB hub or into your keyboard, plug it directly into one of the USB ports on the computer. If it works there, the issue is with the device to which it had been previously connected. The device may need more power than the port provides.
6. Not all USB ports in the computer are working
Check the device in all the USB ports on the computer. Also test each port using a good, working USB device. Sometimes one port on the computer will stop functioning, but others will still work. If this is the case, the computer may need to be serviced.
7. Does the device have a power cord?
Does the affected device have a power cord? If it does, try unplugging and replugging it. Make sure it's plugged into a working power outlet (you can test the outlet by plugging in a lamp or clock).
8. Check if the device is properly mounted:
1. Open Hard Disk > Applications > Utilities > Disk Utility.
2. Highlight the name of your device, if it shows Mount on top, click Mount so that it changes to Unmount.
Before you begin
Software to edit video clips free download. You can resolve many display issues by updating the software on your Apple devices, cables, and adapters. If you can see an image on your screen, check for software updates using the Mac App Store:
- Connect your external display and any Apple video cables or adapters that you use with it.
- From the Apple menu, choose App Store.
- Click the Updates button in the App Store window.
- Install any macOS or firmware updates that are listed.
If you're using a display, hub, extender, or adapter not made by Apple, check with the manufacturer for any updates that might be available.
If you're trying to connect a 4K display or Ultra HD TV with your Mac, make sure your computer meets the requirements for using these external displays.
If your software and firmware are up to date, or if you can't see the image on your screen, try the steps below for your specific issue.
If the display image is blank or unusable
Try these steps if you don't see an image on your display. These steps can also help if the image on your screen repeatedly turns on and off (flickers), if horizontal lines appear (snow), or if the image is distorted (torn or scrambled).
These steps likely won't help if the issue is only happening in one app. If you see similar issues in only one window or app, check with the app's developer for updates or more help.
Check connections
Check the connections to your Mac and external displays:
- If you're using an Apple notebook, try connecting its power adapter.
- Make sure the external display's power cable is securely connected and that your display is turned on.
- If you're using a Mac Pro (Late 2013) make sure your displays are connected to the right ports.
- If you're using a display hub, switchbox, or 'KVM,' try connecting your display's video cable directly to your Mac instead.
- Disconnect the video cable where it plugs into your Mac, then plug it back in to reseat the connection.
- If you're using a video adapter, unplug the video adapter from your Mac, then plug it back in to reseat the connection.
- If you're using more than one video adapter to connect your display (the adapters are 'chained' together), try connecting the display using only one adapter if possible. Some video adapters can't be connected together. For example, a mini DisplayPort to DVI adapter can't be connected to a DVI to HDMI adapter.
- If your display has more than one video connection, see if using another connection on the display works. If possible, check to see if using a different display or a different adapter works.
- Try using a different cable that you know is in working order. Check with the display's manufacturer to make sure you're using the cable they recommend.
- Restart the Mac with the display connected.
Detect your display
If you're using an external display, sleep and wake your Mac to make it check for connected displays:
- Press the power button on your computer to put it to sleep, or choose Apple menu > Sleep.
- Wait a few moments, then press a key on your keyboard or click your mouse or trackpad to wake your Mac.
If you're using more than one display, and you can see the image on one of the displays, you can also use Displays preferences to check for connected displays.
Adjust video settings
If there's no image on your display, try adjusting your display's brightness or contrast. If there's still no image, or the image appears torn or scrambled, try selecting a different video resolution in System Preferences.
Adjust brightness
Macbook Not Recognizing Flash Drive
- If you're using an Apple Display, press the increase brightness key on your Apple keyboard. To adjust the brightness of a secondary display, press Control-F2.
- If you're using a display that's not made by Apple, check the documentation that came with your display to see if it includes built-in controls for adjusting its brightness or contrast.
Change your display resolution
- From the Apple menu, choose System Preferences.
- Click the Displays icon.
- Click Default for display. If you see more than one resolution listed, choose a resolution and refresh rate. If the display turns off when you change resolutions, press the escape key to undo the change.
If you can't change the resolution of your display because you can't see an image, restart your Mac in safe mode to reset the display resolution to defaults.
If starting in safe mode doesn't resolve the issue, reset your Mac's NVRAM and SMC to reset the video ports on your Mac to their defaults.
Check for third-party display software
Macbook Pro Not Recognizing Usb Cable
If your display works only when your Mac is started in safe mode, and you have display-related software installed, check with the software's developer for updates, or try temporarily uninstalling it.
If an image appears fuzzy or blurry
Macbook Pro Not Reading Usb
If images or text on your display appear pixelated or blurry, check these things.
Check your display resolution
Macbook Won't Recognize Usb
Make sure your display resolution in System Preferences is set to its default. If you're using a resolution that's scaled, the image might be magnified to fit the display. This can cause the image to look blurry in some apps.
- From the Apple menu, choose System Preferences.
- Click the Displays icon.
- Select Default for display.
If you use a monitor or an HDTV connected with an HDMI cable, you might see a difference in video quality if your display is set to television mode. Check your display for a 'monitor mode' setting to get the best video quality.
Retina displays
If an app you're using appears low resolution on your Retina display, check to see if an update to the app is available. Most apps have been updated to use the higher pixel densities of Retina displays.
Lower-resolution images on some web pages might also appear 'softer' when viewed on a Retina display. This is because Retina displays have a higher pixel density and not all websites use Retina-ready images.
For example, the images below look different when viewed on a Retina display, but the same on a non-Retina display. This happens because the Retina-ready image has a higher pixel density:
If you see contrast or color issues
If your entire display image seems too dark or too bright, you can adjust the brightness and contrast from the Displays pane of System Preferences, or by using your display's built-in controls.
Adjust brightness and contrast
To adjust the brightness of your Apple display, press the brightness key or F2 key on your keyboard. You can also use the brightness adjustment for each connected display in System Preferences > Displays.
Displays not made by Apple sometimes have brightness and color adjustments built into the display. Check the documentation for your display to see if it includes built-in controls.
When you connect a display, projector, or HDTV using an HDMI cable, you might see a difference in video quality if your display is set to television mode. Check your device for a 'monitor mode' setting to achieve the best video quality.
You can also calibrate each display from the Color tab of Displays preferences to get the best color and brightness from your display.
If you see bright or dark pixels
If individual pixels on your display seem too bright or too dark, see these articles for more help: https://herevload263.weebly.com/sourcetree-merge-conflict-tool.html.

Connecting displays with Thunderbolt 3 (USB-C)
The Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter connects Mac models with Thunderbolt 3 (USB-C) ports to older devices that use Thunderbolt (10Gbps) or Thunderbolt 2 (20Gbps). For example, this is the adapter that you should use to connect your MacBook Pro to an Apple Thunderbolt Display or a third-party Thunderbolt 2 storage device.
This adapter doesn't support connections to Mini DisplayPort displays, including the following Apple adapters and displays:
- Apple Mini DisplayPort to Dual-Link DVI Adapter
- Apple Mini DisplayPort to DVI Adapter
- Apple Mini DisplayPort to VGA Adapter
- Apple LED Cinema Display
If you're using the Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter to connect to a compatible display and the display doesn't show an image, try unplugging the adapter and plugging it back in.
Get more help
If you've tried these steps and your display still isn't working, contact Apple Support to get more help.
Diagnostic fees may apply for issues not covered under warranty or the AppleCare Protection Plan (APP).
Get a data lifeguard for Mac
Disk Drill brings deleted files back from the dead.
Most of the time, when you connect an external hard drive to your Mac's USB port, you soon see it mount on the desktop. Apple likes to ensure these are easy to find, so they also appear in the Finder in the left-hand column under Devices, since Mac's treat them the same way as another computer.
However, sometimes, an external hard drive doesn't show up. It's annoying, especially when you need to transfer something right then. And besides, there can be a risk that data on the external USB pen, hard, or flash drive is corrupt, which means you can't transfer what you need between devices at all.
Corrupt data can be one reason your Mac won't recognize an external drive, but there are other reasons too. Let's take a look why this is happening and how you can get an external drive to appear on your Mac and get recover data to access to your documents.
How to fix an external disk drive that won't show up on a Mac
Why an external disk drive is not showing up? There could be a few reasons why a USB flash drive isn't making an appearance.
Open an External Drive Not Showing on Mac
Get a huge set of top utilities for troubleshooting external hard drives not mounting on a Mac
Start with the basics:
- Check whether the drive is properly plugged in. It sounds obvious, but since this relies on a wire - either a USB cable or HDMI cable - if it's not connected properly then it won't appear on your desktop.
- Faulty cable. Assuming it's plugged in correctly, not wobbly or loose, the cable could be at fault. Try connecting the same device with a different cable.
- Damaged USB or flash drive port. It could be a hardware issue with the Mac. If you've got another port, try connecting the device to that one.
- Reboot your Mac. Sometimes, if a USB disk won't boot, the cause is macOS issue. Hopefully, some data damage that can be fixed by restarting. Choose the Apple menu > Restart. Or press and hold the power button and, when a dialog box appears, click the Restart or press R. Restarting your Mac essentially clears your macOS's memory and starts it up fresh.
- Incorrectly formatted drive. Not every external drive is optimized for Macs. It could be that you are trying to connect something only fit to interact with Windows devices. If you've got a PC or laptop, it's worth connecting and seeing if you can access the files through another device. The best way to look for an incorrectly formatted drive is to go to
Apple (in the top toolbar menu) > About This Mac > Storage.
See if the external drive shows up here. For more information, go to the same menu option, then select System Report. - Mac not formatted to display external drives on the desktop. It could be that your Mac already recognizes the device, but just isn't showing its icon on the desktop screen. Even if that is the case, the drive will still appear in the left-hand column of the Finder menu under Devices. You should be able to access your drive that way, and, in the Finder menu under Preferences > General, you can check External Drives to ensure that from now on it shows up on your desktop too.
- Reset NVRAM. To do this, shut down or restart your Mac, switch it back on and immediately press these four keys together for at least 20 seconds: Option, Command, P, and R. It should look as though your Mac has started again; if it has, release the keys when you hear the second startup chime. Hopefully, the hard drive has shown up now.
- Check Apple's Disk Utility to see if an external drive is showing up. Disk Utility is within System Preferences, or you can find it using Spotlight. If it is visible, then click the option to Mount, which should make it visible on the desktop and in the External Drives option in the Finder menu.
Unfortunately, if none of those options has worked and the external drive still isn't visible, then it could have crashed, or be well and truly broken. But there might still be a way you can recover the data on the external drive.
How to show connected devices in Finder
- Go to the Finder menu and select Preferences (Cmd+comma).
- From General tab tick External disks to ensure that from now on it shows on the desktop.
In the Sidebar tab you can choose which folders and devices will be shown in the left-hand column of the Finder window. Mcafee agent 5 6 3.
How to add cloud storages to Finder
You can also mount cloud storage as local drive on your Mac. By connecting Google Drive, Dropbox, or Amazon to your computer, you get more space for securely accessing and sharing files. For your ease, add cloud drives to Finder with CloudMounter app, so that you keep them close at hand. You can read detailed instructions on managing cloud storage as local drives here.
Repair the failed external drives with First Aid
If your drive is having problems, you can try to fix them yourself with First Aid and therefore get access to your files. First Aid tool will check the disk for errors and then attempt a repair as needed. It helps to verify and repair a range of issues related to startup HD and external drive problems. If you are able to fix the hard drive or SSD in your Mac (or an external drive) using Disk Utility you will hopefully be able to recover your files.
To run Fist Aid on an external hard drive:
- Open Disk Utility. You can searching for it using Spotlight Search or via Finder > Application > Utility
- Check on your external hard drive, click the First Aid tab and select Run to start running diagnostics.
Apple tools download only. If First Aid successful in fixing errors, the external drive should be available to mount. If the utility unable to repair issues, your drive truly is broken or formatted using a file system that the Mac cannot read - in this way we suggest you follow the next steps to recover data from a damaged disk drive.
How to recover data from a crashed drive
Thankfully, there is an app for that. Disk Drill is the world's premier data recovery software for Mac OS X. Powerful enough to retrieve long-lost, mistakenly deleted files from Macs, external hard drives and USB drives and camera cards.
Get a file recovery app
With Setapp you get a pack of professional tools for file recovery and Mac maintenance.
An easy way to recover lost files on an external hard drive
Providing you already have Disk Drill Pro version, which you can get automatically by downloading from Setapp:
- Connect your drive to the Mac.
- Quit all other applications on the Mac, especially those that may be trying to access the external drive (e.g. iPhoto, Words)
- Launch Disk Drill.
- Click on the external drive that you are trying to recover files from. If it has partitions, you will see all of them. If, however, you still don't see any volume to the external drive then you may need to try some of the steps above again or read the Disk Drill Scanning FAQs.
- To avoid the external drive being accessed during the recovery process, click Extras next to the drive or drive partition or file, then select Remount Volume As Read Only. A padlock will appear, protecting the drive during the process.
- Now click Rebuild (or Recover) next to the file(s) you are trying to recover. Once the scan is finished - it may take some time if the files are large - a list of files will appeal.
- Next, click Mount Found Items as Disk button on the bottom-left below the scan results.
- Disk Drill 'strongly suggest saving the files to a different drive than the one you are trying to recover files from. Saving to the same drive substantially lowers your chances of recovery.'
- A drive icon will appear, which once you double click will give you the option to open the files as you would do before they were lost. Drag them to another location, such as your desktop or a folder on your Mac.
- Open the files to ensure they have been recovered properly and safely eject the external drive.
Disk Drill does have other ways to recover lost files but assuming there aren't complications, this method is the most effective. Disk Drill Pro recovery app is available from Setapp, along with dozens of Mac apps that will make your life easier. Never have to worry about a crashed or corrupted external drive again.
A few more tips on getting your files back
- Macs and third-party apps that look after Macs, such as Disk Drill and iStat Menus come with a S.M.A.R.T. (also known as Self-Monitoring, Analysis and Reporting Technology) status monitor. If a SMART check reports errors, then it could mean the hard drive is at risk of failing completely. Within Disk Utility and Disk Drill, there are several solutions for this: Repair Disk Permissions and Repair Disk. If neither work, it's recommended that you backup all of the data from the disk, erase, then run a SMART check again. The external hard drive should show up as Verified.
- Partitions can get lost within hard drives, temporarily hiding all of the information contained within. Disk Drill can help to identify and restore this information.
- Within Disk Drill, you can restore data when a hard drive is damaged or add formatting, which is also something Disk Utility can help with.
- CleanMyMac, another useful app available from Setapp, can help you identify external hard drive errors and repair them. It is an essential tool worth trying when you're having external hard drive difficulties.
Try all these apps for free
Get a huge set of top apps for keeping your Mac in shape. Best utilities in one pack, give it a go!
Alternative ways to recover data from an external hard drive
Reset the System Management Controller (SMC) if your Mac shuts down when you plug in an external hard drive. Then use a different port to connect the external hard drive. If you've got a battery that you can't remove:
- Shut down and unplug the power adapter
- Press Shift-Control-Option and the power button at the same time. Do this for 10 seconds
- Release all keys
- Plug the power adapter back in and switch your Mac back on
For Macs with removable batteries, you need to switch them off, remove the battery, then press and hold the power button for 5 seconds. After that, put the battery back in, plug in the power adapter and switch the power on again.
What's your file format? One reason your Mac isn't recognizing the hard drive is the file format. Windows uses NTFS file formats, while Macs, up until the introduction of Sierra, have used HFS+. Now, Apple has introduced the Apple File System (APFS) for newer operating systems. It is possible to format a hard drive so it can be read on Mac and Windows computers, providing you format using exFAT. However, if you're having problems accessing the files and the issue is due to formatting, you will need to connect it to a device it can be read on, and then format the files correctly for the computer you are going to use it on next.
How to make Ext2/Ext3 drives readable on Mac
The common issue is Ext2- and Ext3-formatted drives are not readable on macOS. There are two ways to access such external drives on your Mac – via Linux OS or FUSE system. The easiest would be installing Linux to a secondary drive or virtual machine.
If you go with Linux installation, dual boot your Mac with Linux on another drive and use FAT32 as a transfer intermediary. If you don't have a drive to install Linux to, use virtual machine as an interface for it. Transferring can be done the same way – with FAT32, or via network.
Another option for reading Ext2/Ext3 disks is mounting disk with Filesystem in Userspace (FUSE). Basically, it works as an extra interface enabling file system access via specially installed modules. Here's how to mount drives with FUSE:
- Install FUSE for macOS or MacFUSE as well as fuse-ext2 module.
- Use the following Terminal command to enable Disk Utility's debug menu and see all partitions: defaults write com.apple.DiskUtility DUDebugMenuEnabled 1
- Attach your Ext2/Ext3 drive and locate the device name via Disk Utility.
- In your user account, create a folder to be used as a mount point.
- Use the following Terminal command to mount the drive as read-only: fuse-ext2 /dev/disk2s2 /Volumes/mountpoint
- For write support, use the command: fuse-ext2 -o force /dev/disk2s2 /Volumes/mountpoint
And that's not the only case where Terminal helps you access external drive.
Employ the handy all-powerful Terminal, which always comes forward with solutions for difficult problems. Especially if System Information does recognize the USB or hard drive, but continues to hide it from you, disconnect the drive and try to find it using the Terminal, which you can find in Applications > Utilities.
New Macbook Pro No Usb
- Once in the Terminal, type in the command diskutil list
- A list with information about volumes and drives should appear
- Look for a section labelled /dev/disk_ (external, physical)
- Make a note of the whole line after the word disk
- Now put the following command into the Terminal diskutil info disk followed by the number or digits assigned to that disk
- Now you should see detailed information about the drive, therefore confirming that your Mac can and does recognize it
- Eject using the Terminal by entering the command diskutil eject disk followed by the number or digits assigned to that disk
- Physically remove the disk from you Mac
- Plug it back in and your Mac should recognize it
Console is also reliable when it comes to solving tricky problems, although it isn't always that easy to use. You can find Console under Applications > Utilities > Console. Console shows if an external drive or any error is detected under the Errors and Faults tab. If no errors show up, then the problem is not caused by the device.
To sum up, there are lots of potential solutions for a Mac not reading an external hard drive. If we were to pick one, Disk Drill seems to be the most well-rounded, offering plenty of customizations and power in an easy-to-use interface. Disk Drill Pro recovery app is available via Setapp, along with 150+ Mac apps that strive to make your life much much easier. At the very least, you'll never have to worry about a crashed or corrupted external drive ever again.
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