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   How to Migrate to a New Mac

   Joe Kissell

   When you get a new Mac ' whether it's brand new or just new to you '
   one of your first questions is bound to be how you move all your data
   from your old Mac (or PC, if you're switching platforms) to the new
   one. Those of us who have moved from one Mac to another repeatedly may
   not give it much thought, but if you haven't done it before, or at
   least recently, the prospect of dealing with loads of documents,
   folders, accounts, preferences, and so on can seem daunting.

   In fact, there are several ways to migrate your data, and which way you
   choose depends on your circumstances. There are four main paths you
   might consider. In order from easiest to most challenging, those paths
   are:
     * Sync from the Cloud: If you keep pretty much all your data in the
       cloud, all you need to do is log in to the appropriate accounts on
       your new Mac. Those accounts would cover documents in iCloud Drive,
       Dropbox, Google Drive, or whatever; email in an IMAP or Exchange
       account; contacts and calendars stored in CardDAV and CalDAV
       accounts; photos synced with iCloud Photo Library or comparable;
       music via streaming or synced using iTunes Match; and so on. Data
       that's cached locally will sync automatically, and anything you
       normally leave in the cloud will remain there, just as accessible
       as it was on your old Mac. Migration is essentially a non-issue,
       except for any random files you stored only on your old Mac's drive
       ' and you can copy those over to the new Mac manually.
     * Use a Clone to Migrate: If you have or are willing to make a
       bootable duplicate, or clone, of your old Mac onto an external hard
       drive using a utility such as [1]Carbon Copy Cloner or
       [2]SuperDuper, you can then connect the duplicate to your new Mac
       and boot from it. (Hold down Option on startup and select the
       duplicate ' see '[3]macOS Hidden Treasures: 15 Startup Key
       Combinations,' 1 September 2016). Now use the same backup utility
       to clone the duplicate onto the startup volume of your new Mac.
       Finally, reboot your new Mac from its internal drive. That's it '
       your new Mac has all the same apps, files, and other data as your
       old one.
       This is the approach I nearly always take, because it's simple,
       it's relatively fast, and it puts all my data exactly where I
       expect it to be. But, there are a couple of caveats. First,
       migrating via a clone assumes that the new Mac can run the same
       operating system that's on your clone. But if your old Mac was
       running, say, Mavericks and you get a new Mac that requires Sierra
       or later, this procedure will leave you with a Mac that doesn't
       boot. You can usually avoid this problem by upgrading your old Mac
       to the very latest system software before cloning it. And second,
       don't use this approach if you've already created files on the new
       Mac because it will overwrite everything on that Mac's drive.
     * Migrate via Setup Assistant: When you turn on a brand new Mac for
       the first time, a program called Setup Assistant runs; it walks you
       through creating a user account and various other essential
       first-run steps. One of those steps offers to transfer your data
       from another Mac, a Time Machine backup, an external startup disk,
       or a Windows PC. If your new Mac requires a newer operating system
       than what's on your old Mac, using Setup Assistant is your best
       option ' and you can still use your old system's clone as a source
       if you like. Setup Assistant also runs when you install macOS onto
       a blank volume, giving you the same options. So, if you're
       performing a clean install of a new operating system, as opposed to
       an in-place upgrade, you can use this procedure to migrate your old
       data.
     * Use Migration Assistant: Finally, there's another utility included
       with every Mac called Migration Assistant, which can be used to
       migrate accounts and data from another Mac (or a backup) at any
       time. Migration Assistant looks and acts almost exactly like the
       file transfer portion of Setup Assistant, which is no accident '
       they use the same underlying code. If you've already been using
       your new Mac for a while, this may be your best option, but, for
       reasons I'll explain in a moment, it's not ideal in every
       situation.

   If one of the first two options (cloud sync or using a clone) meets
   your needs, you can stop reading now. The remainder of this article is
   for people who need to use Apple's migration technology via Setup
   Assistant or Migration Assistant. But before I launch into the steps
   you'll take, I want to give you some essential background on migration
   that may affect your decisions.

   Understand Migration Concepts -- Migration is merely a fancy word for
   copying ' a familiar, ordinary, everyday task that shouldn't seem scary
   at all. Whenever you make a backup, you copy stuff from one place to
   another, just as when you share files over a network. You have stuff on
   your old computer, and you're going to copy it onto your new one. No
   big deal ' but there is quite a lot of copying to be done, and it has
   to be done in just the right way for best results.

   Migration essentially involves two parts:
     * Connecting the two computers: This can be a simple matter of
       stretching a Thunderbolt or FireWire cable between them, or having
       them on the same Ethernet or Wi-Fi network. If you can't do either
       of those things, you can clone everything from the first computer's
       disk onto an intermediate external hard drive and plug that into
       the new Mac.
     * Figuring Out Where the Old Stuff Needs to Go: Figuring out which
       stuff from the old computer needs to go where ' and with which
       attributes (such as ownership and permissions) on the new Mac is
       trickier than it sounds, because some of your data may be hidden in
       databases or invisible folders, or may consist of numerous
       components scattered around your drive, as is often the case with
       applications.

   The migration technology Apple baked into Setup Assistant and Migration
   Assistant knows how to copy stuff from your old computer to your new
   one. It knows where your old stuff is, where it should go, and how to
   copy it intact ' even if locations and file formats have changed from
   your old computer to your new one. It handles the tricky bits so you
   don't have to worry about them. It even simplifies the process of
   making a connection, in that you don't need to mess with file sharing
   settings or mounting network volumes; at most you'll have to run an app
   on the source computer and click a few buttons.

   So far so good. But there's a big difference between transferring stuff
   via Setup Assistant (in the process of setting up a brand new Mac or
   installing macOS on an empty volume), and running Migration Assistant
   manually later. With Setup Assistant, you're starting from scratch,
   creating accounts on your new Mac based on the data from your old Mac.
   But with Migration Assistant, you're adding to what's already on your
   new Mac. And that leads to the crucial issue, which I want to
   emphasize:

   Migration Assistant can't merge accounts.

   Here's what I mean. Say I've brought home a new Mac, and I've gone
   through its Setup Assistant to set up a new user account with a full
   name of Joe Kissell and a short name (or 'account name,' which is also
   the name of my home folder) of joe ' for the logical reason that, well,
   that's my name and it's what I used on my old Mac or PC (Windows uses
   only long usernames). And I start saving files, adding calendar
   entries, and doing all the usual things I do. A week later, I decide to
   migrate the data from my old Mac or PC, which will include all the
   files in my main user account there. But when I try, Migration
   Assistant gives me some bad news: I can't migrate the data unless I
   change the account name, because every full and short username must be
   unique on a given Mac, and the new Mac already has an account called
   Joe Kissell, or joe for short!

   So I could rename the account I'm transferring to Joseph Kissell with a
   short name of joseph or jk or whatever. But then I have something I
   don't want ' two accounts:
     * My new Joe Kissell account, which uses the name I want, and which
       has the data I've created since I set up the account a week ago
     * My old account, which was called Joe Kissell but has now been
       renamed to Joseph Kissell, and which contains all my old data

   If Migration Assistant could somehow merge all the stuff from my old
   Joe Kissell account into my new one, there'd be no problem. But it
   can't! And sure, I could come up with a complicated procedure to merge
   the accounts manually, but it would be an awful lot of error-prone
   work. Not fun.

   The moral of the story is: When you get a new Mac, or when you do a
   clean installation of macOS, the optimal time to migrate your old stuff
   (in order to keep account names intact) is right away, during that
   first run of Setup Assistant, instead of later, using Migration
   Assistant.

   If it's already too late ' you've already set up a new account with a
   conflicting name ' you have three choices, the first two of which can
   beperformed by Migration Assistant, as I'll describe shortly:
     * Keep the existing account as is, and rename the old one as I
       described above. If you're not especially tied to the old username,
       this might seem like a perfectly reasonable choice, but then you'll
       have files under two different accounts, which is awkward at best.
     * If you've created relatively little new data yet in the new
       account, you can replace the account with the conflicting name '
       that is, overwrite all the data from the newer account with the
       data from the account you're migrating while saving a copy of the
       overwritten data. If you already have important data under the new
       account, you can retrieve it later after logging in to the migrated
       account. This option is available when migrating from an account on
       another Mac, but not when migrating from a Windows PC.
     * Change the short (and long) name of the new account so it won't
       conflict, transfer the old account, and manually copy data from the
       new one to the old one, deleting the new account when you're done.
       If you want to do this, you can find [4]instructions for the
       name-change part on Apple's site, but I'm afraid you'll have to do
       the actual data copying part manually. And, since you can't
       normally access another user's home folder, you'll have to use the
       /Users/Shared folder, an external drive, or some command-line magic
       to work around that restriction.

   Having said all that, I should point out that using Migration
   Assistant, including the version in Setup Assistant, is not an
   all-or-nothing affair. You can use it to transfer only your
   applications, for example, or only particular user accounts, or only
   certain types of data from a user account. Although most people want to
   transfer everything, it's entirely up to you.

   With that background in mind, I'll walk you through three scenarios:
     * Migrating data from an old Mac via Setup Assistant during the
       initial setup of a new Mac, or after a clean install of macOS
     * Migrating data from an old Mac via Migration Assistant to a Mac
       that already has one or more active user accounts and data you
       don't want to lose
     * Migrating data from a Windows PC

   Migrate from Another Mac Using Setup Assistant -- If you are
   transferring data from another Mac while running Setup Assistant on a
   brand new Mac ' or during a clean installation of macOS onto a blank
   volume ' follow these steps:

   1: If you're using a brand new Mac for the first time, work your way
   through Setup Assistant until you get to the Transfer Information to
   This Mac screen. Similarly, if you've just installed macOS onto a blank
   volume, follow the prompts until you get to this screen.

   [5][tn_MigrationTransferMac.jpg]

   2: Select 'From a Mac, Time Machine backup, or startup disk.' But don't
   click Continue yet.

   3: Make sure the old Mac, or the drive on which your Time Machine
   backup or bootable duplicate exists, is connected to your new Mac:
     * Mac-to-Mac: If both Macs have Thunderbolt ports, your best bet is
       to connect a Thunderbolt cable to each. If not, but both Macs have
       FireWire ports, use a FireWire cable. If one has Thunderbolt and
       the other has FireWire, you can use a FireWire cable with [6]a
       Thunderbolt-to-FireWire adapter. If neither Thunderbolt nor
       FireWire is an option, use an Ethernet cable. And, if even that
       isn't possible because you're using a Mac with no Ethernet port and
       don't have a [7]USB-to-Ethernet adapter, make sure the Macs are on
       the same Wi-Fi network ' but bear in mind that Wi-Fi will nearly
       always be much slower than the other options.
     * Backup Drive: If you're transferring information by way of a
       backup, make sure the backup drive is connected to the new Mac. If
       you backed up to a Time Capsule using Time Machine, connect the
       Time Capsule to the Mac via Ethernet if possible; if that isn't
       possible, move the Mac as close as you can to the Time Capsule for
       better Wi-Fi reception.

   4: If you're using a Thunderbolt or FireWire cable, turn off the old
   Mac, and then turn it back on while holding down the T key. This puts
   it in Target Disk Mode, which means it functions as an external hard
   drive.

   If you're using an Ethernet cable or a Wi-Fi network, then on the old
   Mac, open Migration Assistant, from /Applications/Utilities. Follow the
   prompts until you get to the Migration Assistant screen. Select To
   Another Mac, and click Continue.

   [8][tn_MigrationAssistant.jpg]

   5: Back on the new Mac, click Continue.

   6: Select the source from which you'll be transferring your data (often
   there will be only one choice), and click Continue.

   [9][tn_SelectSource.jpg]

   Note the following qualifications:
     * Mac in Target Disk Mode or bootable duplicate on an external drive:
       If your source disk is encrypted with FileVault, the Continue
       button becomes Unlock. Click it and enter the disk's password.
     * Mac connected via Ethernet or Wi-Fi: You'll see additional prompts
       on both Macs for passcode verification. Once you've confirmed that
       they're the same, click Continue on the source Mac.
     * Time Machine backup on a Time Capsule or an external drive: After
       you select the source and click Continue, you must select the
       backup (typically, there will be only one) and click Continue
       again. If prompted, also select the backup volume and click
       Continue.

   7: Select the kinds of data you want to transfer. The screen shows the
   size of each item, and the total size of the selected items ' along
   with available space on your destination volume ' updates automatically
   as you change your selections. It may take a few minutes for the
   installer to initially display and calculate the sizes of each option.

   [10][tn_SelectInformationToTransfer.jpg]

   If the volume you're transferring from has just one user account, you
   may see only three checkboxes, all selected by default: Applications,
   Documents & Data (with an accompanying Edit button), and Computer &
   Network Settings. If the volume has more than one user account, as
   shown above, you'll see a scrolling list that contains numerous items '
   again, all selected by default: Applications, each user account listed
   by name, an 'Other files and folders' entry, and Computer & Network
   Settings.

   Here's an explanation of each option, and my recommendations:
     * Applications: This option transfers the contents of your previous
       /Applications folder and its subfolders, such as Utilities,
       skipping any applications for which the new Mac already has newer
       versions: Safari, Mail, and so on). Because you may find it tedious
       to reinstall your applications, leave this option selected, as it
       is by default.
       If you select Applications, Setup Assistant also copies the
       contents of /Library on your previous system. This is extremely
       good, because that folder contains many support files without which
       some apps wouldn't run. Aswith /Applications, Setup Assistant won't
       copy any older files over newer versions it has just installed.
     * Documents & Data: If you have just one user account, you'll see a
       checkbox labeled Documents & Data ' this refers to the data in your
       user account. Click Edit to view its contents. In the dialog that
       appears, you can deselect any top-level folder within the account,
       except for the Library folder. Along with the visible top-level
       folders is a folder called Other Data. Apple doesn't specify what
       this includes and my tests to find out have been inconclusive, so I
       suggest leaving it selected just in case it contains anything you
       need. Finally, there's a checkbox labeled 'Other files and
       folders.' This option refers to any files or folders at the root
       level of your old volume as well as anything in the /Users/Shared
       folder. I suggest leaving this checkbox selected.
     * User accounts: If you have more than one user account, each is
       shown at the top level of the list.
       This list may include 'users' that don't have a conventional user
       account or home folder on your Mac, but which your Mac considers to
       have an account of a sort ' people with whom you've shared files
       using System Preferences > Sharing, for example, or special
       low-level accounts added by software such as MacPorts or Cloak (the
       cloakproxy account). Some of these may display messages about
       having no home folder or having a home location that is relocated.
       Don't worry about these messages; Setup Assistant is merely
       pointing out that these won't create conventional user accounts,
       each with its own home folder. It's best to leave such user
       accounts selected, even if they appear to contain no data.
       Transferring a user means copying the user's entire home folder,
       ifany (/Users/some-username), to the new Mac; once a user is
       transferred, the user can log in without having to set up an
       account again. You should transfer all existing user accounts
       except those are no longer in use. You can, if you like, deselect
       any individual (top-level) folders within a user's home folder to
       skip copying those to your new Mac. As for the unexplained Other
       Data folder that I mentioned in the previous bullet point, the
       safest course is to leave it selected.
     * Other files and folders: As in the single-user account setting
       described in the second bullet point, this option refers to any
       files or folders at the root level of your old volume as well as
       anything in the /Users/Shared folder. I suggest leaving this
       checkbox selected.
     * Computer & Network Settings: This category sometimes has up to
       three sub-items that you can select. Computer includes certain
       system-wide settings, such as sharing preferences, Energy Saver
       settings, and parental controls. Printers refers to your printer
       settings. Network includes the settings in your Network preference
       pane. I suggest leaving Computer & Network Settings checked, along
       with all sub-items that may be present.

   After making your selections, click Continue.

   Setup Assistant copies the selected items to your new Mac ' a process
   that may take just a few minutes or several hours, depending on how
   much data you are transferring.

   Be aware of the following:
     * You should completely disregard any time estimates you see '
       they're notoriously and often ludicrously inaccurate.
     * If Setup Assistant notices any software conflicts with the files
       you've selected, it displays an Incompatible Software warning
       notice and moves the conflicting items to an Incompatible Software
       folder at the top level of your startup volume. Click Continue to
       keep going.
     * If FileVault was enabled on the volume you're migrating data from,
       Setup Assistant reminds you that it's not enabled automatically on
       your new volume ' but that you can enable it manually.

   At the end of the migration process, a Migration Complete screen
   appears, stating that your data has been migrated and is ready to use.
   Click Quit to dismiss the window. At this point, your Mac should prompt
   you to log in, and then ask you a few final questions.

   Migrate from Another Mac Using Migration Assistant -- If you've already
   set up a new Mac and you want to migrate data from an old Mac, the
   process is almost the same as what I just described, but with two
   modifications:

   1: On the new Mac, open Migration Assistant from
   /Applications/Utilities. Follow the prompts until you get to the
   Migration Assistant screen shown earlier.

   2: Pick up with Step 2 in the previous set of instructions. But when
   you get to Step 6, if you've selected a user account on the source Mac
   whose name (short or long) overlaps with one already on the destination
   Mac, a message appears underneath the list of items to transfer: 'Some
   conflicts were detected. Finish selecting the information you'd like to
   transfer, then click Continue to fix any conflicts.' When you click
   Continue, you'll see the dialog shown below.

   [11][tn_MigrationUserConflict.jpg]

   As I discussed earlier, you can select either:
     * Replace 'User Name' on this Mac: This choice removes the account on
       the destination Mac with the conflicting name. Happily, if you
       leave 'Keep a copy of the data from this Mac' selected, as it is by
       default, Migration Assistant saves the account's data in the
       Deleted Users subfolder of the Users folder, so you can retrieve
       any needed files later.
     * Keep Both User Accounts: To keep both accounts, enter a new full
       name and User Account (short) name for the account you're about to
       transfer from the other Mac.
       Make your choice and click Continue. Migration Assistant copies the
       selected data. When it finishes, you can quit it on both Macs. You
       may be prompted to restart the destination Mac or to log back in.

   Migrate from a Windows PC -- The steps for migrating your data from a
   Windows PC using Migration Assistant are similar to what you would do
   in a Mac-to-Mac transfer.

   A tip: If you're doing this during the installation of macOS, you don't
   need to jump through so many hoops. Specifically, follow Steps 1'3
   below, and then, when Setup Assistant asks you where to transfer files
   from, select 'From a Windows PC' and click Continue. Then skip ahead to
   Step 9, and pick up from there.

   The steps to migrate from Windows to macOS are as follows:

   1: Make sure the PC and the Mac are on the same Wi-Fi or, better yet,
   Ethernet network.

   2: On the PC, [12]download the Windows Migration Assistant and install
   it.

   3: Run Migration Assistant on the PC and click Continue twice, which
   brings you to a screen that says Searching.

   [13][tn_MigrationAssistantWindowsSearching.jpg]

   4: On the Mac, open Migration Assistant from /Applications/Utilities.

   5: Follow the prompts until you get to the Migration Assistant screen.

   6: Select 'From a Windows PC' and click Continue.

   7: Select the Windows PC as the source. In most cases you'll see only
   the PC on which you're running the Windows Migration Assistant, but if
   you see more than one, select the one you want. Click Continue.

   8: A passcode will appear on both your Windows screen and your Mac
   screen. Verify that the number is the same on both sides, and then, on
   the Windows PC, click Continue.

   [14][tn_MigrationAssistantWindowsPasscode.jpg]

   9: Back on the Mac, select the kinds of data you want to transfer. Your
   options are:
     * Users: Each user account on the selected PC appears here, and all
       are selected by default. You can leave everything checked to
       transfer all the data to its corresponding location on your Mac, or
       deselect any of the folders at the top level of a user's home
       directory (such as Music, Desktop, and Documents) as well as
       Contacts, Bookmarks, Calendars, and Settings. As when transferring
       data from another Mac, if you select a user whose name matches the
       full username of an account on your Mac, you'll be asked to choose
       a new full name for the transferred account.
     * Other Files on C: This category, which may or may not appear
       depending on your configuration, includes other folders on your
       main Windows volume you may want to transfer, including Shared
       Files. They're all selected by default, but you can deselect any
       you don't care about.

   10: After making your selections, click Continue.

   The file transfer proceeds. When it's finished, click Quit in Migration
   Assistant on the Windows PC, and follow the prompts on the Mac to
   complete setup.

   Final Advice -- As I noted earlier, the process of transferring files
   is far, far easier if you do it immediately upon unpacking your new
   Mac, or if you're willing to overwrite the new Mac entirely from a
   bootable duplicate.

   That said, if you're reading this because you need to merge the
   contents of an old Mac onto a new Mac that you've been using for some
   time, I hope the advice above helps.

References

   1. http://bombich.com/
   2. http://www.shirt-pocket.com/
   3. http://tidbits.com/article/16712
   4. https://support.apple.com/en-us/HT201548
   5. http://tidbits.com/resources/2016-09/MigrationTransferMac.png
   6. http://www.apple.com/shop/product/MD464LL/A/apple-thunderbolt-to-firewire-adapter
   7. http://www.apple.com/shop/product/MC704LL/A/apple-usb-ethernet-adapter
   8. http://tidbits.com/resources/2016-09/MigrationAssistant.png
   9. http://tidbits.com/resources/2016-09/SelectSource.png
  10. http://tidbits.com/resources/2016-09/SelectInformationToTransfer.png
  11. http://tidbits.com/resources/2016-09/MigrationUserConflict.png
  12. https://support.apple.com/kb/DL1557
  13. http://tidbits.com/resources/2016-09/MigrationAssistantWindowsSearching.png
  14. http://tidbits.com/resources/2016-09/MigrationAssistantWindowsPasscode.png