Apple’s Mail and most email clients on every platform and from every third party optimize their defaults settings around leaving mail on a server. That’s the modern way, where we can reach the same mail storage on any device, as well as through web mail.
However, it’s possible to avoid all this. You just have to change a view settings and rethink how you file mail once you’ve dealt with it. You can archive messages on a single Mac and store them there without leaving a copy on the server but you’d better be making backups, Time Machine or otherwise, or you’ll be sunk if your drive fails.
Your Inbox will always remain on the server. The Inbox is essentially a window into messages that have arrived and you haven’t processed. You make one change in settings and one change in behavior for everything else.
In Mail in macOS, follow these steps:
• Select Mail > Preferences and click Accounts.
• Select iCloud in the list at left.
• In the Account Information tab, set Download Attachments to All (the only reason to avoid this if you get frequent large attachments in messages you delete without needing those attachments).
• In the Mailbox Behaviors tab, for each mailbox popup menu, select a mailbox listed under On My Mac (if no mailbox exists, you need to create it from the Mailboxes sidebar).
Now all the standard Mail behavior will result in messages being downloaded or stored on your Mac.
On the behavior side, create all the mailboxes you need under the On My Mac section of the Mailboxes list, and then as you receive email in your Inbox, file those locally into those folders. That removes the messages from the mail server, leaving it stored only on your Mac.
If you’ve been using FileVault from the time you set up your Mac, that encryption is extremely strong, and erasing the drive deletes the passphrase-protected encryption key. That makes the contents effectively irretrievable, and no additional erasure is needed for an SSD or HDD. If you didn’t use FileVault, here are your options.
Unless you’re dealing with secrets that would lead to the overthrow of governments, using Disk Utility’s secure erase feature meets the mark. HDDs can also be physically destroyed with a drill equipped with a bit suitable for puncturing the metal casing. A hammer and chisel could work, too. If you have a dead HDD and if you think anyone with motivation might pay to have the data recovered, physical destruction is the only way to ensure data isn’t readable.
Data is written in an unpredictable fashion on SSDs to distribute the wear across all the memory cells in the solid-state device. As a result, a secure erase feature doesn’t work at all, as it may not overwrite all the data. Physical destruction is really the only course of action, which is an unfortunate waste of technology. And if you have a Mac in which the SSD isn’t removable, but part of the computer, that’s even worse.
Fortunately, the various kinds of RAMs used by generations of Macs are all volatile memory: the contents disappear instantly or shortly after a device is powered down. So far, there’s no way to recover any traces of data from RAM chips.
One of the good things about Reminders app is that it allows you to set due dates and times with each task you enter. You can set these times and dates manually, or you can use natural language expressions with the app to set up your time-sensitive tasks a lot more quickly. Here’s how to do it.
Launch Reminders and select a list of reminders you want to add tasks to, or create an entirely new list. Then, click on the little Plus icon in the upper right; this should create a spot for you to make a new reminder. Now, type in your natural language request, like "Meeting with John tomorrow at 11:30".
Reminders will create the actual task, but will also set up a notification to let you know when the event is about. You don't have to create the reminder, select the info button, and put in the details one at a time.
First you need to physically copy the picture library to the new location, and then you have to tell Photos where the new location is. Here's how to do this:
• Go to the Pictures folder (in your home directory) and locate the "Photos Library" package
• Copy the "Photos Library" package to the new destination by dragging and dropping it to the desired location
• Hold the Option (Alt) key down and launch Photos
• Find the Photos Library in the list or click the "Other Library…" button to manually navigate to the new location and then click the "Choose" button
Now Photos will use the library you have specified in the new location. Be aware that if the library is located on an an external hard drive and you launch Photos without that drive connected, your images won’t be available.
Mac users in higher security risk situations may wish to enable an optional firmware password on their machines, which offers an advanced level of protection. In short, a firmware password is a lower level layer of security that is set on the actual Mac logic board firmware, rather than at the software layer like FileVault encryption or the standard login password.
The result of setting an firmware password is that a Mac can not be booted from an external boot volume, single user mode, or target disk mode, and it also prevents resetting of PRAM and the ability to boot into safe mode, without logging in through the firmware password first. This effectively prevents a wide variety of methods that could potentially be used to compromise a Mac, and offers exceptional security for users who require such protection.
Like any other essential password, use something memorable but complex, and do not forget a firmware password after it has been set. A lost firmware password is unrecoverable on most modern Macs without a visit to an Apple Store for service and recovery.
Setting a firmware password is rather simple.
• Start up from macOS recovery mode by holding down Command (⌘)-R immediately after turning on your Mac. Release the keys when you see the Apple logo.
• When the utilities window appears, choose Utilities > Firmware Password Utility from the menu bar. On iMac Pro, choose Startup Security Utility instead.
• Click Turn On Firmware Password.
• Enter a firmware password in the fields provided, then click Set Password.
• Quit the utility, then choose Apple () menu > Restart.
The firmware password will not appear during a regular restart or boot of the Mac, it only becomes mandatory when the Mac is attempted to boot from alternate methods. This may be in situations where a Mac is attempted to boot from an macOS installer drive, an external boot volume, recovery mode, single user mode, verbose mode, target disk mode, resetting the PRAM, or any other alternative booting approach that will summon the rather plain looking firmware password window. There are no password hints or additional details provided, only a simple lock logo and a text entry screen. An incorrectly entered firmware password does nothing and offers no indication of login failure except that the Mac won't boot as anticipated.