Mac Startup Disk is Full?

Your startup disk is almost full mac

What does “Your startup disk is almost full” mean?

The warning message indicating that your startup disk is almost full appears when there is no longer enough free space on your disk. This is often due to having too many files occupying your Mac’s hard drive, bringing free space to a dangerously low level.
To resolve this issue, you need to free up some disk space.

How does “Startup Disk Full” affect your Mac?

Lack of free space on the startup disk leads to both unstable and slow performance of the macOS system. It can also prevent applications from being able to launch or work properly, including suddenly crashing or simply ceasing to work.

What to do if the startup disk is full on Mac

In general, you need to clean up your startup disk to recover some space. You can either remove some files manually or use MacCleaner Pro to perform this task quickly and easily.

Also, you can upload some large files to the cloud or offload them to a backup disk, however, this approach requires you to have additional storage. For the system to work properly, you will need to free up from 10 to 30 Gigabytes by removing unneeded files.

How to check startup disk on your Mac

Follow the next steps to see what kind of files eat your startup disk space.

  1. Click About This Mac menu at the Apple menu
  2. Click the Storage tab
  3. Review the storage usage to see what files are eating up space.


storage space

There are seven general categories of data stored on your Startup Disk. The larger the bar, the larger the space taken up by those types of files: Photos, Apps, Movies, Audios, Backups, Documents, and Other.

Now you know what types of files are taking up space on your Mac startup disk. Usually movies, pictures or backups take up the most space. But it often happens that the biggest space eaters are the “Other” files, including caches, logs, cookies, archives, disk images, plugins, extensions and so on.

You can remove unneeded files manually or use special software tools for quick and easy disk cleanup.

How to Clean up Mac Startup Disk

  1. Check Your Trash

It may sound elementary, but we frequently delete files and forget to empty the Trash. The files in the Trash still occupy your disk space, so it is recommended that you empty the Trash folder at least once a week.

To delete files from the Trash folder permanently, right click on the Trash in the dock panel and select Empty Bin. Another way to complete this task is to open the Trash and click the Empty button in the top right corner.

  • free up space on mac
  • how to free up space on mac

  1. Delete Downloads

How many times have you downloaded files from web browsers, messengers, torrents, and mail? When you download files from the Internet, by default they are saved in the Downloads folder, which can easily be found at this location:

/Macintosh HD/Users/Current User/Downloads

startup disk is full According to statistics, the average user accumulates 0.5 GB per week in the Downloads folder.

All of the files in the Downloads folder usually remain unorganized and may take up several Gigabytes of free space. While you may have needed to retrieve files very rarely, for example, installation files (disk images), more than half the files in Downloads are not needed and should be deleted.

Sorting the list of files by size, kind, or date will help you to quickly find out which unneeded files you have and remove them.

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  1. Clear Cache

A cache file is a temporary data file created by apps, browsers and many other programs to help your Mac run faster. Note that when you remove cache files, they will be recreated the next time you run the application. Even so, it’s a good idea to clear the cache from time to time. Apps you may no longer be using, as well as their leftovers, still remain in the Cache folder and occupy tens of gigabytes of your disk memory.

Cache files are stored in the Library folders, which you can find in the following locations:

  • /Library/Caches
  • ~/Library/Caches

In /Library/Caches you will find temporary files created by the system. Usually these files don’t occupy too much space. However, in the ~/Library/Caches folder, you will see a huge number of junk files, which are created when you run applications. As a result, this folder may increase substantially in size over time.

 other storage on mac

By default, the Library folder is hidden on macOS, as Apple keeps there system files and protects them from accidental removal. To open it, follow these steps:

  1. Open the Finder window.
  2. From Menu click Go → Go to Folder.
  3. Type ~/Library/Caches in the dialog box and click Go.
  4. Keep the folders, but go into each one and delete the files inside.
mac disk cleanup
Important! Cache files with an “apple” in the name cannot be deleted. Deleting such files may cause a system crash.

  1. Remove Logs

While the Library folder is open, you can also find another type of temporary file – log files. They are stored in the Logs folder. Please make sure that before you remove system logs, apps and mobile devices, you no longer need them.

how to free up space on your mac

  1. Remove Language Resources

Language Resources is the data stored by apps for different languages. Apart from English, lots of apps include languages such as German, Chinese, French, Portuguese, Italian, Korean, Russian, Hindi, and others.

For instance, Spotify has 54 languages. If you don’t need all of these translations, you can get rid of unneeded ones from within the Spotify Contents folder. Follow the steps below to remove unneeded language files:

  • Open the Applications folder → select Spotify → right-click and select Show Package Contents.
  • In the window that appears, select Resources and delete useless language files. Generally these files have the first two letters of a particular language and an .lproj extension.
language resources on mac Using this method, you can remove all unused languages in your applications. Be careful to only delete certain language files, since deleting important application files can affect the app’s performance or even lead to a crash.

Note! English is the base language, so you should never delete it.

  1. Delete Mail Downloads

If you use the standard macOS Mail application, the system saves them to a separate folder on your hard drive. After several months of using the mail client, the folder’s size can grow up to several GB.

The easiest way to find this folder is to search via Spotlight. Just type “Mail Downloads” in the search field.

Delete mail downloads on mac If this method didn’t work, then open the Finder → press Shift+Cmd+G key shortcut and in a search field enter:


how to delete temporary files on mac Preview the files and save those that you need, or delete all the files at once.

All previous steps can be easily done by MacCleaner Pro. MacCleaner Pro will automatically find all junk files and allow you to remove them in just a few clicks. The software tool will find all junk files in just a few seconds: Downloads, Trash, Cache, Logs, and Language Resources.

  1. Launch MacCleaner Pro.
  2. Click to clean up on junk files.
    clean up mac
  3. Take a look at the junk files and select unneeded types.
  4. Then click on Review & Remove and confirm removal.
    clean up junk files

  1. Delete Old iPhone Backups

If you sync your iPhone with iTunes often, the application creates dozens of backup copies on your device. These copies consume a significant amount of disk space, as they include movies, music, and other large files. To find old backups, launch iTunes → Go to Menu Bar → iTunes → Preferences.

Here you will see a list of all the backups iTunes managed to make while working with your device. If you are sure that you do not need them, safely remove them. But first make sure they are stored in iCloud!

startup disk full macbook pro Another way to find and remove iOS backups is to go to the following location:

~/Library/Application Support/MobileSync/Backup

how to clear up disk space on mac

  1. Uninstall Unused Apps

Check your Applications folder. The number of all the installed applications may sometimes exceed 100; in fact, some may not be used regularly or even at all. These apps take up a lot of space on your Mac’s hard drive. So it’s time to uninstall such unused programs.

But please note, moving an app to the Trash just by dragging and dropping it is not enough. You need to remove the app’s cache and other service files, which are stored in the Library folder. We recommend that you read the instructions on how to uninstall apps completely or use a special tool from MacCleaner Pro – App Cleaner & Uninstaller. It will help you to remove apps both correctly and completely.

Instead of manually searching for apps’ service files and wasting your time, App Cleaner & Uninstaller will automatically find all the service files and even the leftovers of previously-removed apps.

mac app cleaner

  1. Remove Leftovers

Leftovers are the broken service files left after deleting the apps. Such broken service files are unnecessary and they just take up your disk memory, so you should find and remove them.

The apps’ leftovers are usually stored in the Library folder; however, they sometimes can be scattered in different locations all over your drive, littering your Mac. Searching for them manually seems to be an impractical task. Fortunately, with the help of App Cleaner & Uninstaller, you can find and remove them with ease. The application finds and shows these files in the Remaining Files section.

remove remains

  1. Move Large and Infrequently Used Files to External Drive

If you need to free up gigabytes of data, the best way to do it as quickly as possible is to check out your Movies folder. Video content is the biggest space eater, as well as audio and photo files in the Music and Pictures folders.

Also check your disk for other files with large sizes. For this, go to File in the Menu Bar and select New Smart Folder.

your startup disk is full

In the top right corner click the Plus button and, in the parameter fields, select File Size … is greater than, and set the needed file size, for example, 1GB or 500MB. Preview the largest files and remove/move unused ones.

disk full mac Even if you have removed the largest files, like videos or music, you may still have lots of other huge files you don’t suspect. We recommend that you analyze your disk space usage deeper and find out what’s taking up the most space on your disk. For this, you can use another tool from MacCleaner Pro- Disk Expert.

Disk Expert shows you the disk space usage in a sunburst diagram and allows you to easily manage the biggest files and folders.The app is capable of scanning custom folders, identifying the largest files, and collecting files from various folders into unified “drop lists” for transfer to external hard drives.

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  1. Use Cloud-Based Data Storage Services

If you use the Dropbox service, you know that even with the free version the service provides two complimentary gigabytes of space. This means that you can move big files and folders from your hard drive to cloud storage. Use the Selective synchronization option, which allows you to delete content sent to the cloud from the hard drive. To do this, go to the Preferences → Sync section and specify the desired folders to sync.

startup disk is full mac Besides Dropbox, there are dozens of other similar services you can use, such as Google Drive, iDrive, Microsoft SkyDrive and so on.

  1. Delete Unnecessary Desktop Pictures and ScreenSavers

Most Mac users like good screensavers and do not limit themselves to the default collection. If you are a screensaver fan and have a collection of them, don’t forget that they may take up sizable memory space on your disk. It is recommended that you remove unneeded screensavers. For this purpose, you can again use App Cleaner & Uninstaller Pro, which finds all the screen savers and shows them in the Extensions section.

free up memory on mac

To find the desktop wallpapers, go to the following directory:

/Macintosh HD/Library/Desktop Pictures

how to manage storage on mac It contains 52 images of 432.52 Mb. You are free to delete all redundant pictures.

  1. Find and Remove Duplicate Files

You may have created copies of documents or downloaded some files twice, and later forgotten about it. Duplicate files take up useless disk space on your Mac. Searching for duplicates manually seems to be a long and hard process. The only thing you can do very quickly is to find the duplicate media files (music and video) in the iTunes Library.

To find duplicate music and video files, follow these steps:

  • Open iTunes.
  • Click the File in the Menu.
  • Select Library → Show Duplicate Items.

iTunes will show you a list of duplicates. Examine the list and remove the duplicates.

delete duplicate on music Unfortunately, for all other types of duplicate files, you will have to look through each folder individually. This could take hours. But don’t panic; there is a solution. We will now discuss another way to find duplicates, and we are sure you will find it useful.

For other types of duplicate files, use the appropriate tool from MacCleaner Pro- Duplicate File Finder, which will help you to find and remove duplicate files in less than five minutes.

Duplicate File Finder allows you to scan any folders and drives and find all duplicate files, including videos, music, pictures, documents, archives and other duplicate files. The application finds even similar folders and can merge them, making it easy to organize your files and folders.

program to find duplicate files

  1. Restart Your Mac

Once you’ve cleaned up your hard drive, you should restart your Mac. A simple rebooting of the system can help to free up the disk space cluttered by temporary items and cache folders. It will also clear the virtual memory and sleep image files.

how to clean startup disk

  1. Clear Ram Memory on Your Mac

And, finally, it’s time to think about your RAM memory as well. This will not only create more space on your Mac, but will also help speed it up. This is especially important when your startup disk is almost full and your Mac’s speed is starting to lag. Use Mac Cleaner Pro when it comes to speeding up your Mac.

  1. Go to the Performance section or click on Speed up Mac in the sidebar.
    mac performance
  2. Select Free up RAM and click on Review & Speed Up button.
    free up ram mac

If your Mac is still slow, you can use additional speedup options in MacCleaner Pro to make your Mac run faster. Also, launch the special tool, Memory Cleaner, that works in the background and automatically clears inactive RAM when memory space is filled.

Now no more “Startup disk full” message will disturb you

Well, that seems to be all. Using these tips, you can delete up to 20 GB of unneeded data from the computer. We hope these tips help you to free up disk space on your Mac and fix the “Startup Disk is Full” error message. Just note that you can clean up your Mac manually, but this may take too much time. Also, you can use professional tools, which save time and perform a quick, efficient cleanup of your hard drive.


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