If you've just purchased a new Mac, and you are upgrading from an older computer, you want all of your files and data to be accessible on the new machine. But when you generate a new Mac, in the event you migrate your old files or do a clean installation?

When you get a new Mac, it might be a good idea to do a clean installation; beginning with scratch, having a brand-new operating-system, and duplicate the files that you need from your old Mac manually. Here's how to migrate your files for your new Mac, or perform a clean installation, and also the benefits and drawbacks of both methods.

How emigrate files to a new Mac

Apple features a useful tool included in macOS: Migration Assistant. This selection is comparable to Setup Assistant, which only runs during the setup of a new Mac; therefore, if you have setup your Mac is new, you'll have to use Migration Assistant to copy files from whether backup or a different Mac.

When you place up a new Mac, the Setup Assistant purports to copy your files. To use this tool on a Mac, do among the following:

  1. Connect two Macs using a Thunderbolt or Ethernet cable, or get them to both attached to the same wi-fi network.
  2. Connect the brand new Mac to a hard disk in which you have cloned your startup volume , or hook it up to some drive you’ve employed for Time Machine backups.
  3. Connect the Macs using target disk mode; see this Apple support document for additional on target disk mode.

Select the Mac or hard disk from which you need to copy data, and then select which kind of data you need to transfer-user accounts, applications, other files and folders, and settings-and wait while the files get copied.

As you can observe, Migration Assistant is easy to use. It copies all of your files, and you can choose which user accounts get copied to the new Mac.

However, the disadvantage of using the Migration Assistant is the fact that all of your files get copied. This is often a disadvantage if you've been upgrading your Macs through the years by installing new versions of macOS over original copies, or migrating data from old Macs to new ones, you will have hundreds, even a large number of old files that you simply no longer need taking on space. For this reason, you might like to consider carrying out a clean installation.

Clean Installation

When you do a clean installation, you let macOS run its Setup Assistant and make up a new, empty user account. During the process, you enter some information, such as your Apple ID, so that your iCloud account is activated, but, typically, your Mac will be a tabula rasa-a blank slate. It'll retain the default apps which are a part of macOS, but nothing more.

If you go this route, you then need to manually copy files from your old Mac, or from the backup. This area of the process can be time-consuming, but it can allow you to definitely sift through your files to find what you really need, and slim down your Mac. With this option, you might be surprised to locate what you can ignore out of your old Mac.

Here's what you ought to copy after a clean installation:

Applications: macOS installs numerous applications, many of which you most likely use every single day. Included in this are Safari, Mail, Calendar, Music, Photos, and the iWork apps . However, you probably use lots of other apps on your Mac. If you have purchased apps in the Mac App Store, you'll need to re-download them; they won’t work if you copy these apps in one Mac to another. However for apps you've purchased from developers, it can easier to copy them manually. And this is an excellent time to choose which of the numerous apps inside your Applications folder you need to keep. You might find a large number of apps that you simply rarely use. If that's the case, don't copy them.

Your Home Folder: you need to copy most of the files out of your home folder . You won't want to copy the folders at the very top level of your house folder-Desktop, Documents, Downloads, Movies, Music, and Pictures-but rather the items in these folders into the identically-named folders around the new Mac. Again, take this opportunity to check on whether you have to keep all of the files during these folders.

Your Library Folder: there is a special folder in your home folder called Library. Automatically, this folder is hidden, but it contains many files that you should copy. For instance, all your email is in this folder, out of the box the information in the Contacts app. First, you need to access this hidden folder on the new Mac. Within the Finder, press the Option key, and select Go > Library. In another Finder window, navigate to the old Library folder. If it’s not visible, press Command-Shift-G, then enter, for instance, /Volumes/backup-disk-name/Users/your-user-name/Library, and click on Go. You'll have two windows open.

Here are some of the folders that you want to copy in the old Library folder to the new one; though if you sync a lot of data with iCloud, then most of the folders below will already be populated together with your up-to-date data:

  • Application Support; though look inside this folder, and just copy folders for apps you're still using. Note that if you’re syncing data via iCloud, lots of this data will already be available, so check the folders around the new Mac and don’t overwrite ones that contain data that is up to date.
  • Containers; this contains data for many apps, both from Apple and third-party developers.
  • Group Containers; as above, it has data from many apps,
  • Calendars
  • Fonts
  • HomeKit; this has HomeKit settings, if you use those features.
  • Music; this might contain AppleScripts, if you have used any using the Music app.
  • Keychains; this contains all your stored passwords.
  • Mail; this contains all of your email, as well as your email settings.
  • Preference Panes; should there be any that you have installed that you still use.
  • Safari; this has your Safari bookmarks.

There’s lots of important data in the Application Support folder. As well as the above folders, it’s smart to copy any folder whose modification date is in the past couple of years. To get this done, choose View > As List, then right-click the window header – where you see columns like Name and Size – and let Date Modified. Click that header, to sort in date order. Start looking in the newest dates and come back. Also, if you see folders with names for apps that you know you will no longer use, then don’t copy them. Do the same for the library folder generally. But, check inside the folders to see if they contain contents with newer modification dates compared to those shown for that folders; this is probably a bug, but a lot of the folders within my Library folder have older modification dates than their contents. One folder you don’t need to copy is /Library/Caches; this can be quite large, and your apps will create new caches while you use them.

I don't recommend that you copy the Preferences folder; this probably contains lots of files for apps you will no longer use. I do, however, suggest that you go through that folder and duplicate over any files or folders for apps that you do use, particularly if, when you launch them, their setup is different. However, you may just want to manually reset the preferences for your apps; this is an excellent method to rediscover your apps as well as their interfaces.

You'll notice, as you start working using the new Mac, that you will need to enter ghd serial numbers its the apps that you didn't purchase from the Mac App Store. This is because many apps store invisible files on your Mac for registration purposes, and also you haven't copied these. So be sure you know where your serial numbers are.

As you work in your new Mac, you may find that certain files are missing. Because of this you need to absolutely not delete your old backup, and especially the ~/Library folder. You may want to go back into that folder and copy some other files to the new Mac.

While I don't recommend carrying out a clean installation for every new Mac you get, or for each macOS update, it's a good idea to get it done every couple of years. Just make sure to keep a backup in case there are any files you need to find that you didn't copy within the first time around.

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