Flash, or thumb, drives are a great way to transfer data between multiple computers. And every once in a while, this transfer method fails because flash drives are physical devices. They can be damaged or have data corrupted.
However, more often than not, the problem is not with the device itself, but how we use them. If the USB flash drive appears to be corrupted, e.g., when Mac cannot detect it or refuses to mount the drive, make sure that it was properly prepared.
- To learn how much power a drive requires, connect it to your Mac, open the System Information app (in the Applications folder's Utilities folder), click USB in the sidebar, select the drive in the USB Device Tree at the top, and then read the Current Required line.
- What to do if the Mac's internal hard drive is not recognized. Undoubtedly one of the most scaly situations we can have on our Mac is when we open it and a folder with a question mark appears. In these cases when we should start to shake because it means that the Mac is not recognizing the hard drive correctly and it is possible to start from it.
macOS has a built-in tool that can help fix an unreadable USB flash drive on Mac: Disk Utility. After selecting the drive in the Disk Utility, click on the First Aid button to verify the device. However, before fixing the problem, check if the drive was correctlyformatted.
How To Fix Unreadable USB Flash Drive On Mac
Find the word 'Devices' in the upper-left side of the Finder window. If your USB flash drive has been correctly inserted, there will be a temporary drive icon labeled with the name of your USB flash drive. Temporary drive icons are white, while permanent drive icons. Numerous advanced tips can be used to make sure that the user gets the best results when it comes to USB usage on a Mac. This tutorial will discuss the top 7 tips for using a flash drive. It will also provide a basic level of training to make the overall use of flash drive easier for Mac users. 1 Connecting Flash Drive to MAC.
Verify the USB drive was formatted for compatibility with macOS
There are two special cases when a USB drive may not be accessible, but not because it was corrupted. It is possible that the drive was not formatted in a disk format compatible with macOS. The two cases are:
- A new drive
- The drive that has been used in Windows or another operating system
Formatting the new drive
Most flash drives that you can purchase are preformatted in the Windows format (because there are more PC users than Mac users). In some cases, the drives were not formatted at all.
If the USB drive was not formatted, then the first time you plug it into the Mac, you will see the error message 'The disk you inserted was not readable by this computer' with the options to Initialize, Ignore and Reject.
If the drive was never used before (and does not contain any valuable data), then click on the Initialize button. This will open the Disk Utility app.
Another way to open the app is to use the Spotlight Search: press simultaneously Command and Space bar keys and type 'Disk Utility' in the search bar. Hit Enter.
On the left side of the app, locate the flash drive. Since this is a brand new drive, it won't have partitions like this:
Microsoft office 2019 mac price. Click on the Partition button in the top toolbar of the app.
You need to provide three pieces of information: Name, Format, and Size. Ignore the size and use the default.
Type a meaningful description in the Name field (I usually avoid using special symbols, underscores, and spaces).
When it comes to the format, there are many choices, and the choice depends on how the flash drive is going to be used.
If you are absolutely sure that the flash drive will only be used with Mac computers, and there will never be a need to copy something to and from PC, then the best format is Mac OS Extended Journaled.
Boot To Flash Drive Mac
If you need encryption, then use the encrypted version of the format. However, do not use case-sensitive variants: I don't know a single case when it could be useful.
In case there is a possibility, even a remote one, that the flash drive will be used with Windows computers, then pick ExFAT.
Here is a file format compatibility table from my previous post:
Formatting a drive used with PC
As you can see from the table above, Macs support most PC formats, while PC only supports its own ones. macOS fully supports FAT32 (appears as MS-DOS in the Disk Utility) and ExFAT. Mac tools dealer locator.
The problem with MS-DOS format is that it was intended to store files less than 4GB. In other words, if the file is formatted as MS-DOS device, you will not be able to copy files larger than 4 GB on it.
Where Is My Flash Drive On Machine
Macs can also read from drives formatted as NTFS, but only in read-only mode. Macs cannot delete or modify the file contents on NTFS drives.
Unfortunately, if the drive was already formatted with NFTS, the only way to reformat for read/write Mac compatibility is first to save the contents of the drive on another computer or disk, reformat to ExFAT, and then copy the files back to drive.
Verify the USB drive was mounted in Mac
One issue that beginner users often face is when the USB drive won't mount on Mac.
To find out if the drive was mounted, again, use the Disk Utility. Sometimes, the drive will appear in the list of volumes (or disks) on the left side of the app but does not appear in the Finder.
In this case, select the drive and then click on the Mount button in the toolbar.
If the drive was mounted, but you can't see it on the Desktop, then try another trick. Right-click on the drive in the Disk Utility and choose the 'Open in Finder' option from the drop-down menu.
Run First Aid from Disk Utility app
As mentioned above, macOS has a built-in tool to check and repair failed devices. In the Disk Utility app, select the problem drive and then click on the First Aid button.
The tool will pop up a message box.
Click on the Run button. First, the First Aid module will check if the device has any problems. If any errors found, it will ask for permission to fix the errors.
Reset PRAM on Mac
There is a universal solution for the most problems with any Mac. It's called resetting PRAM (Parameter RAM).
The PRAM contains some initialization parameters related to hardware cached in the special memory. Mkv player mac 10 6 8. Sometimes, this memory gets corrupted and may cause all kinds of problems with sound, video, and USB devices.
All you need is to shut down Mac first. Then turn it on and immediately hold four keys on the keyboard: Command, Option, P, and R. Release the keys once the Apple logo appears on the screen.
Here are the detailed instructions from Apple.
Try 3rd party drive recovery apps
Where Is My Flash Drive On Mac Computer
If nothing from above helped with the issue, one way to try to solve the problem is to use 3rd party apps.
I cannot recommend any apps, but if you decide to go with this route, I have some suggestions on how to make sure that the app is safe.
I always suggest using apps downloaded from the Mac App Store.
However, the problem is that the apps from the App Store usually have restrictions when it comes to direct access to the hardware (kind of thing you need when the device is failing).
So, it is most likely that the apps that can recover USB drives have to be downloaded directly from the developer site, which is not safe.
To make sure that the app does not contain any malware or adware, upload the file to Virus Total web site. This site will run multiple antivirus scanners, and if it does not find anything, then the downloaded software is most likely clean.
Send the drive to Mac repair shop
It happens very rarely so that the USB flash drive is actually having problems, e.g., bad sectors. The issue was prevalent with older mechanical devices that had moving parts, and they used to get worn out. Nowadays, it most likely that the connector could break or deform.
I have a 10-year old thumb drive, which is hard to unplug. When I try to pull it out from the USB port, I often pull the outer case, but the connector stays inside the port.
But, if you exhausted all DIY methods, it is probably a time to ask help from a specialist. I know a number of Mac repair shops that specialize in data recovery. They have a number of expensive tools they can run and diagnose the disk problems.
In conclusion, I wanted to note that quality matters when purchasing USB flash drives.
Anyone who thinks they found a good deal on Amazon – a thumb drive with a lot of space under $10-$20 with thousands of five-star reviews, but the company name is unknown or hard to pronounce, is risking to lose their data one day.
The quality devices may cost a little extra, but they have two distinct advantages:
- They are less likely to fail
- They are 3-4 times faster than no-name brands
If you are looking for suggestions, check my page with the best USB flash drives (type A and C):
Photo credit: ©canva.com/Svetlana Lukienko
Optimized Storage helps you save storage space space by storing your content in iCloud and making it available on demand:
- When storage space is needed, files, photos, movies, email attachments, and other files that you seldom use are stored in iCloud automatically.
- Each file stays right where you last saved it, and downloads when you open it.
- Files that you've used recently remain on your Mac, along with optimized versions of your photos.
If you haven't yet upgraded to macOS Sierra or later, learn about other ways to free up storage space.
Find out how much storage is available on your Mac
Choose Apple menu > About This Mac, then click Storage. Each segment of the bar is an estimate of the storage space used by a category of files. Move your pointer over each segment for more detail.
Click the Manage button to open the Storage Management window, pictured below.
Manage storage on your Mac
The Storage Management window offers recommendations for optimizing your storage. If some recommendations are already turned on, you will see fewer recommendations.
Store in iCloud
Click the Store in iCloud button, then choose from these options:
- Desktop and Documents. Store all files from these two locations in iCloud Drive. When storage space is needed, only the files you recently opened are kept on your Mac, so that you can easily work offline. Files stored only in iCloud show a download icon , which you can double-click to download the original file. Learn more about this feature.
- Photos. Store all original, full-resolution photos and videos in iCloud Photos. When storage space is needed, only space-saving (optimized) versions of photos are kept on your Mac. To download the original photo or video, just open it.
- Messages. Store all messages and attachments in iCloud. When storage space is needed, only the messages and attachments you recently opened are kept on your Mac. Learn more about Messages in iCloud.
Storing files in iCloud uses the storage space in your iCloud storage plan. If you reach or exceed your iCloud storage limit, you can either buy more iCloud storage or make more iCloud storage available. iCloud storage starts at 50GB for $0.99 (USD) a month, and you can purchase additional storage directly from your Apple device. Learn more about prices in your region.
Optimize Storage
Click the Optimize button to save space by automatically removing watched movies and TV shows. When storage space is needed, movies or TV shows that you purchased from Apple and already watched are removed from your Mac. Click the download icon next to a movie or TV show to download it again.
Your Mac will also save space by keeping only recent email attachments on this Mac when storage space is needed. You can manually download any attachments at any time by opening the email or attachment, or saving the attachment to your Mac.
Optimizing storage for movies, TV shows, and email attachments doesn't require iCloud storage space.
Empty Trash Automatically
Empty Trash Automatically permanently deletes files that have been in the Trash for more than 30 days.
Reduce Clutter
Reduce Clutter helps you identify large files and files you might no longer need. Click the Review Files button, then choose any of the file categories in the sidebar, such as Applications, Documents, Music Creation, or Trash.
You can delete the files in some categories directly from this window. Other categories show the total storage space used by the files in each app. You can then open the app and decide whether to delete files from within it.
Learn how to redownload apps, music, movies, TV shows, and books.
Where to find the settings for each feature
The button for each recommendation in the Storage Management window affects one or more settings in other apps. You can also control those settings directly within each app.
- If you're using macOS Catalina or later, choose Apple menu > System Preferences, click Apple ID, then select iCloud in the sidebar: Store in iCloud turns on the Optimize Mac Storage setting on the right. To turn off iCloud Drive entirely, deselect iCloud Drive.
- If you're using macOS Mojave or earlier, choose Apple menu > System Preferences, click iCloud, then click Options next to iCloud Drive. Store in iCloud turns on the Desktop & Documents Folders and Optimize Mac Storage settings.
- In Photos, choose Photos > Preferences, then click iCloud. Store in iCloud selects iCloud Photos and Optimize Mac Storage.
- In Messages, choose Messages > Preferences, then click iMessage. Store in iCloud selects Enable Messages in iCloud.
- If you're using macOS Catalina or later, open the Apple TV app, choose TV > Preferences from the menu bar, then click Files. Optimize Storage selects 'Automatically delete watched movies and TV shows.'
- In you're using macOS Mojave or earlier, open iTunes, choose iTunes > Preferences from the menu bar, then click Advanced. Optimize Storage selects 'Automatically delete watched movies and TV shows.'
- In Mail, choose Mail > Preferences from the menu bar, then click Accounts. In the Account Information section on the right, Optimize Storage sets the Download Attachments menu to either Recent or None.
Empty Trash Automatically: From the Finder, choose Finder > Preferences, then click Advanced. Empty Trash Automatically selects 'Remove items from the Trash after 30 days.'
Other ways that macOS helps automatically save space
With macOS Sierra or later, your Mac automatically takes these additional steps to save storage space:
- Detects duplicate downloads in Safari, keeping only the most recent version of the download
- Reminds you to delete used app installers
- Removes old fonts, languages, and dictionaries that aren't being used
- Clears caches, logs, and other unnecessary data when storage space is needed
How to free up storage space manually
Even without using the Optimized Storage features described in this article, you can take other steps to make more storage space available:
- Music, movies, and other media can use a lot of storage space. Learn how to delete music, movies, and TV shows from your device.
- Delete other files that you no longer need by moving them to the Trash, then emptying the Trash. The Downloads folder is good place to look for files that you might no longer need.
- Move files to an external storage device.
- Compress files.
- Delete unneeded email: In the Mail app, choose Mailbox > Erase Junk Mail. If you no longer need the email in your Trash mailbox, choose Mailbox > Erase Deleted Items.
Learn more
- The Storage pane of About This Mac is the best way to determine the amount of storage space available on your Mac. Disk Utility and other apps might show storage categories such as Not Mounted, VM, Recovery, Other Volumes, Free, or Purgeable. Don't rely on these categories to understand how to free up storage space or how much storage space is available for your data.
- When you duplicate a file on an APFS-formatted volume, that file doesn't use additional storage space on the volume. Deleting a duplicate file frees up only the space required by any data you might have added to the duplicate. If you no longer need any copies of the file, you can recover all of the storage space by deleting both the duplicate and the original file.
- If you're using a pro app and Optimize Mac Storage, learn how to make sure that your projects are always on your Mac and able to access their files.