How can I delete the old Time Machine backup on my Mac to make space for a new one?

markus_1338 wrote:

Soo... I'm pretty much stuck with a full ssd occupied by a unfinished backup and can't find a way to delete the old backup so it can finish the unfinished one, nor can I find a way to delete the unfinished backup.

FWIW, your option is to remove the external drive from Time Machine settings, erase the drive, start a new set of TM backups. A drive used for TM should be 2 to 3 times the size of the drive you are backing up.

As far as CleanMyMac, no experienced Mac user would install it. I wouldn't even if you bought me a Mac to install it on.

TimeMachine has changed since Ventura/Sonoma

It used to work as circular buffers, when needing space on the disk, by clearing older backups. It's not the case anymore, rendering it totally useless.

If you have a 1TB Mac disk and use TimeMachine with an external disk, whether it's 2, 3 or 5Tb it will fill it up and then complain "there isn't enough space [disk name]" instead of cleaning older backups. They even removed the options for TimeMachine, you can' control anything anymore.

it's again one of those changes that breaks things and they don't inform about. The worst is that it's useless to have a "backup" solution that thinks you have endless resources. If you attach a 100PetaBytes disk it will fill it up over months and complain again.

My only solution is to reformat the TimeMachine target disk and start a new first full TimeMachine backup and then wait another 2 weeks until it's full and start over. My Mac has a 1Tb disk and it backs up over a 3Tb dedicated disk. It lasts about 2-3 weeks before being full.

Before Ventura/Sonoma, I never touched it, it was backing up, freeing required disk space (circular backups) and I never heard about TimeMachine.

Talk about a professional solution.

Follow On

As the TM Backup was set to Manual and was left " after some months have passed since the first one. " this would tend to indicate that all the Personal Data is not too important to the User.

Further, leaving ones Important and Non Replaceable Personal Data unprotected is generally not a good idea.

Predicated on the above - you can use Erase and reformat a storage device in Disk Utility on Mac - Apple Support (CA) and Start a New Time Machine Backup Regime from Scratch

Understand - reformatting the Entire External Drive will remove ALL Data from the drive and can not be retrieved under normal circumstance

As for " CleanMyMac " have been installed and used on this computer >>

Specific to CleanMyMac aka “ BrickMyMac “

The steps in #1 below is predicated on the Offending  Application has been Removed as per the Developers Specific Instruction 

#1 - Some Contributors suggest restarting in Recovery Mode and choosing to Reinstall the Operating System over  the existing installation. 

This may or may not replace elements of the Entire Operating System including the Home Folder ( User Account )  and replace any corrupted or removed elements of the Operating System and make thing right.

#2 - Then there are Other Contributors ( like myself ) would suggest  from this link Use Disk Utility to erase a Mac with Apple silicon.

For Intel computer >> Use Disk Utility to erase an Intel-based Mac followed by How to reinstall macOS

Thereafter to start from scratch and install all Required Application directly from the Apple Apps Store or Directly from the Developer.

If going this route - I suggest Not using Startup Assist to migrate things back as this will probably Re-Introduce the existing  issue that existed when the TM Backup was made as this will probably Re-Introduce the existing  issue that existed when the TM Backup was made 

TimeMachine has changed since Ventura/Sonoma

That is the only nearly true statement.

It used to work as circular buffers, when needing space on the disk, by clearing older backups. It's not the case anymore, rendering it totally useless.

It still works that way (well except for the circular buffers thing which I have no idea what you are talking about).

If you have a 1TB Mac disk and use TimeMachine with an external disk, whether it's 2, 3 or 5Tb it will fill it up and then complain "there isn't enough space [disk name]" instead of cleaning older backups. They even removed the options for TimeMachine, you can' control anything anymore.

it's again one of those changes that breaks things and they don't inform about. The worst is that it's useless to have a "backup" solution that thinks you have endless resources. If you attach a 100PetaBytes disk it will fill it up over months and complain again.

Mine hasn't filled up at all. I've got a 5TB drive with two volumes backing up two Macs and it has never filled up.

My only solution is to reformat the TimeMachine target disk and start a new first full TimeMachine backup and then wait another 2 weeks until it's full and start over.

You have something wrong with your Mac or something installed that is interfering with its normal functioning.

markus_1338 wrote:

I'm trying to do a time machine backup, the second one of my macbook on the same external ssd after some months have passed since the first one.

How to delete Time Machine snapshots on your Mac.  

Often caused if the Time Machine Drive has not been attached  to the computer and TM Backup is set to run on a Schedule. 

TM Backup will make Snap Shot on the Internal Drive awaiting the TM Backup Drive to be attached. 

Only then will the Snaps Shots be transferred to the External Drive and deleted the Internal Drive.

The first backup has around 380GB and there were around 400GB free space left on the ssd.

I started the backup of my macbook and now I'm getting the error: "backup not completed - not enough space..."

Now the ssd is pretty much full, in finder I only see the old backup but "clean my mac" is telling me there is a folder with an about 75% done backup "[date]-[some number].interrupted"

Certain Applications maybe available on the Apple Apps Store - this only means the Developer is prepared to pay Apple a portion on each sale. What the Application may do to the computer is up to the User to check this out before purchase

Any of the below should be removed as per Developers Instructions

1 - Disk Cleaner 

This will include CleanMyMac , aka “ BrickMyMac “

Read some of the posting and arrive at your own conclusions.

I can't find a way to manually delete the old backup to free up space, nor does time machine automatically delete the old backup to free up space for the new backup.

Am I doing something wrong, or how am I supposed to go from here?

IMHO - There has been sufficient advise offered, from at last 3 different Contributors, for the User ( you ) to make an informed and educated choice what remedial actions are  required for this computer.

Above is specific to " BrickMyMac " application.

The suggestions have been put forth on a volunteer basis, in good faith and in the best interests of the computer.

markus_1338 wrote:

what's so wrong with clean my mac?

The main problem is any app that automatically modifies the system can have errors that causes it to make changes it shouldn't. There are over 6,000 reports on this forum alone of issues CMM has caused. Some problems that required the clean install of macOS.

TM Backup set to Manual is new and not previous disclosed information

" Now the ssd is pretty much full, in finder I only see the old backup but "clean my mac" is "

+ 1

The problem with lack of space is probably not in the backup drive, but in your system drive.

How much free space in the system drive?