Clean Mac System Data

Before you do anything else try the following.

• Restart in Safe Mode followed by a normal restart.
• Go to About this Mac > Storage > Manage, and follow the recommendations
• If you have Time Machine set up go to System Preferences and turn it off, allow it to finish deleting local snapshots and then turn it back on.
• Get into the habit of regularly turning your Mac off if you normally leave it on for many days.

Let us know if this changes things.

sann83 wrote:

Hello, I am storing almost 50GB in undescribed system data and MacOS on my 2019 MacBook Air "13. I understand this has to do with data collected and not thrown as a result of system updates. I also understand I have to reset my Mac to factory settings.

I have made a backup in iCloud, but I don't know how to proceed with a reset / how to empty my Mac before restoring it.

Thank you for helping,

Q - " I have made a backup in iCloud "

A - Firstly, iCloud is intended to have files in iCloud so changes made on one device are reflected to All your Other devices.

A - It is not designed or intended to be used to Off Load Files in order to make space on the Internal Drive. An External Drive is designed for that purpose

A - As mention earlier use the builtin Time Machine Backup Utility to perform a Backup of all your important data

A - To attempt to clear up space on the Internal Drive >>

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The final word from Apple on Managing the " Other/ System Data “ Category

Other / System Data: Contains files that don’t fall into the categories listed here. This category primarily includes files and data used by the system, such as log files, caches, VM files, and other runtime system resources. Also included are temporary files, fonts, app support files, and plug-ins. You can't manage the contents of this category. The contents are managed by macOS, and the category varies in size depending on the current state of your Mac.