Privacy and security
What Nixt Mail stores and where, what it never does, the app lock, certificates, and erasing everything on this device.
Nixt Mail is built so that your mail stays between you and your mail provider. This page says exactly what the app keeps, where, what it contacts, and how to lock it or erase it.
The short version
- Your mail goes straight between Nixt Mail and your provider. Nixt Mail does not route mail through servers of its own, in any edition.
- Sign-ins live in the keychain. Passwords, app passwords and sign-in tokens are stored in your operating system’s secure credential store, not in a file.
- Nothing about your messages is written to disk unless you turn on offline mail — and then only what you choose, encrypted.
- No analytics, telemetry or crash reports are collected or sent.
- Messages cannot report back. Remote pictures are held back, scripts are removed, and read receipts are never sent unless you choose to be asked and then press Send receipt.
- Nothing contacts a sender unless you press a button — loading images, unsubscribing, or sending a receipt.
What Nixt Mail stores, and where
Below is everything Nixt Mail keeps on this device, and where it lives. Nixt Mail keeps the same list itself: Erase everything on this device works through it, so nothing it stores is left behind.
Where each item is kept:
| Label | Meaning |
|---|---|
| Keychain | Your operating system’s secure credential store: encrypted and tied to this device. |
| On disk | Ordinary app settings. Not secret, and not encrypted. |
| Encrypted on disk | Files in Nixt Mail’s own storage, encrypted with a key kept in the keychain. |
| Your system’s notifications | Held by your operating system’s notification service. |
| Memory only | Held while Nixt Mail is open, and gone when it closes. |
The full list
| Item | Where | What it is |
|---|---|---|
| Mail and calendar passwords, and OAuth tokens | Keychain | So your accounts reconnect without asking you to sign in each time. A connected Google or Microsoft calendar uses the same sign-in as the mail account. |
| Calendar accounts | On disk | The address and server of each calendar account you connected. No passwords. |
| Calendar settings | On disk | How the calendar looks, and which calendars you hid. |
| Calendar on this device | Encrypted on disk | Events you put in the calendar kept on this device, encrypted with a key in the keychain. |
| Events from connected calendars | Memory only | Held while Nixt Mail is open, unless you turn on the calendar’s offline copy. |
| Offline copy of connected calendars | Encrypted on disk | Nothing until you turn on the calendar’s offline copy. Turning it off deletes the copy and its key. |
| Upcoming calendar reminders | Your system’s notifications | Only when calendar reminders come from the system: the next week of reminders, handed to your operating system’s notification service, which keeps them until each goes off. While the app lock is on they say only “Calendar reminder”. |
| AI provider keys | Keychain | The key you gave for an AI provider, if any, held for that one destination. |
| AI permissions | Memory only | What you allowed AI to read and do. Closing Nixt Mail ends every permission. |
| AI summaries you asked for | Memory only | The summary and suggested replies a model wrote for a message you asked it to summarize. Gone when Nixt Mail closes. |
| Account list | On disk | The addresses and server settings of your accounts. No passwords. |
| Signatures | On disk | The lines you put at the bottom of your mail, and the shorter ones for replies. |
| Senders whose images always load | On disk | The addresses you chose to load pictures from, and nothing else about them. |
| Send-from addresses | On disk | The other addresses you said each account can send from, and the names shown with them. |
| Templates | On disk | The text you kept to put into messages, with its names and subjects. |
| Blocked senders | On disk | The addresses and domains you blocked, and nothing else about them or their mail. |
| Senders you sorted | On disk | The addresses you said are a person, or automated mail, so their mail is sorted that way, and nothing else about them or their mail. |
| Automatic replies that are on | On disk | Which accounts have an out-of-office reply on, and its first and last day, so the mail window can say so. Not what the reply says. |
| A skipped update | On disk | The version number of a build you chose not to be told about as Nixt Mail starts. |
| Lock settings | On disk | Whether the app lock is on, and how long it waits. |
| Where AI and services run | On disk | Where each capability runs, and the addresses of your own servers. Never a key or token. |
| Appearance and setup state | On disk | Whether first-run setup is done, your theme, and whether transparency is reduced. |
| Opened messages | Memory only | A small cache of messages you opened, so moving between them does not download them again. Never written to disk. |
| Your preferences | On disk | Your choices in Settings. |
| Snoozed messages | On disk | Which messages you snoozed and when each comes back — an identifier and a time, nothing about the message. |
| Threads marked handled in Autopilot | On disk | Which conversations you marked handled — each conversation’s identifier and when its latest message was sent, nothing about the message. The last 500 are kept. |
| Rules | On disk | The rules you wrote: the words you typed and the actions. No message text. |
| Offline mail settings | On disk | Which accounts and folders you keep offline, and for how long. |
| A conversation you print | On disk, briefly | Windows and Linux only. The conversation is written to your temporary folder so your web browser can open it to print. It is not encrypted, because the browser has to read it, and it is deleted two minutes later. On a Mac nothing is written: it goes straight to the print window. |
| Scheduled messages | Encrypted on disk | Only messages you chose to send later, whole, until they have gone. Encrypted with the same keychain key as offline mail, sent nowhere but your own mail server at their time, and deleted by Erase everything on this device. |
| Offline mail | Encrypted on disk | Nothing until you turn it on. Then only what you chose, encrypted with a key in the keychain, kept for the period you chose, and deleted when you remove the account. |
| Sender logos | On disk | Nothing until you turn on sender logos. Then company logos, fetched once per domain, stored under names that do not reveal the domains. A logo is public, so it is not encrypted. |
| Unsent drafts | Memory only | So closing the composer does not lose your message. Closing it also saves a copy to your own account’s Drafts folder on the server. |
| The message you are writing | Disk, encrypted | With Settings › Composing › Keeping a message safe while you write set to On this device, encrypted (the default): the one message being written, so a crash or a quit does not lose it. Encrypted with the same keychain key as offline mail, never sent anywhere, and removed once the message is sent or discarded, or the setting is changed. |
AI items are described on AI permissions and AI providers; calendar items on Calendar.
What Nixt Mail does not keep or do
- No message bodies, subjects or attachments are written to this device — unless you turn on offline mail, and then only for the accounts and folders you chose, for as long as you chose, encrypted, and going nowhere else.
- No search history is kept while Settings › Message list › Recent searches is off. While it is on, your last eight searches are kept to offer again under the search box, and nothing else about what you searched for; turning it off removes them.
- No analytics, telemetry or crash reports are collected or sent.
- Apart from your own mail servers, and calendar servers you connect, Nixt Mail contacts nothing on its own — except a domain’s website for its logo, once per domain, while Sender logos is on, and the Nixt Office download service, with your licence, while Settings › Updates › Check for updates is set to Each time Nixt Mail starts or Every day.
- Pressing Unsubscribe sends one request to the address the sender put in the message, after a dialog saying where it goes, and only when you press it.
What Nixt Mail connects to
| Connection | When |
|---|---|
| Your mail servers | While Nixt Mail is open, for your connected accounts. |
| Calendar servers | When you connect a calendar account. |
| Google’s or Microsoft’s sign-in service | In your browser when you sign in with Continue with Gmail or Continue with Outlook, and directly from Nixt Mail when it renews that sign-in. |
| Your JMAP server’s sign-in page, in your browser | When you sign in over JMAP. |
| Your own domain’s settings | When you add an IMAP / SMTP account: your domain’s own web server over HTTPS, and its DNS records, to find server settings. No other settings service is asked. |
| A sender’s website | Only with Sender logos on, once per domain; or when you choose Unsubscribe. |
| Remote pictures in a message | Only when you choose Load images, or allow a sender or all senders. |
| AI destinations | Only if you set up AI and agree to send something. See AI overview and Where AI and services run. |
Settings that protect your privacy
Most of these are in Settings › Privacy and security. The rest are in the section they belong to.
| Setting | Default | What it protects |
|---|---|---|
| Privacy and security › Load images from the web | Off | Senders cannot tell when you open their mail. |
| Message list › Sender logos | Off | No company is asked for its logo. |
| Privacy and security › Offer to send read receipts | Off | Senders cannot learn that, or when, you read their mail. |
| Privacy and security › Show where a link goes first | Off | Turn on to see a link’s real address before it opens. |
| Privacy and security › Remove link tracking | On | Tracking added to a link is taken off before it opens. |
| Privacy and security › Warn about fake senders | On | Mail whose name and address do not match says so under the sender. |
| Message list › Recent searches | On | Turn off to keep no searches on this device. |
| Notifications › Notification previews | Sender and subject | Choose Sender only or Only that mail arrived to keep subjects off your lock screen. |
| Composing › Address suggestions | On | Turn off to stop names appearing as you type, for example on a shared screen. |
| Composing › Recipients outside my organisation | Off | Turn on to be asked before mail leaves your organisation. |
| Sync and offline › Offline mail | Off | No mail is kept on this device. |
| Sync and offline › Download messages in advance | On | Turn off to download only what you open. Downloading ahead never marks mail read. |
| Privacy and security › App lock | Off | Turn on to require your device’s authentication before mail is shown. |
| Privacy and security › Unlock before erasing or exporting | On | With the app lock on, erasing everything or exporting your settings asks for it first. |
App lock
The app lock hides your mail behind Touch ID, Windows Hello or your device passcode — useful on a shared or unattended computer, because anyone who can read your mail can reset most of your other accounts. It is off until you turn it on.
Turn on the app lock
-
Open Settings › Privacy and security.
-
Under Lock, turn on App lock. The line under it reads Uses Touch ID, Windows Hello, or your device passcode.
-
Choose Lock after:
Choice Nixt Mail locks when… Immediately …it leaves the foreground. After 1 minute …it has been in the background for a minute. After 5 minutes (default) …it has been in the background for five minutes. After 15 minutes …it has been in the background for fifteen minutes. After 1 hour …it has been in the background for an hour.
With the lock on, the line reads Nixt Mail locks after the time below, and whenever you lock it. Nixt Mail also starts locked every time you open it.
Nixt Mail checks that your device can authenticate before it turns the lock on. If it cannot, the setting stays off and says This device has no passcode or biometrics set up, so the lock would leave you with no way back in. Set up a passcode or biometrics in your system settings first.
Lock now
- Choose Lock now in Settings › Privacy and security (shown while the lock is on), or
- Choose File › Lock Nixt Mail.
Unlock
The lock screen says Nixt Mail is locked — Unlock with your device to read your mail. Under the button it says where the lock is turned off: App lock is on in Settings › Privacy and security. Unlock to change it.
- Choose Unlock. The button reads Waiting….
- Authenticate when your system asks (Unlock Nixt Mail to read your mail).
If authentication fails, the screen says That didn’t unlock. Try again when you’re ready.
What the lock hides
- The whole window, behind the lock screen.
- The menus: on macOS only the Nixt Mail and Window menus remain; on Windows and Linux only File › Exit.
- Notifications: while locked, a new-mail notification says only that mail arrived, whatever Notification previews is set to, and calendar reminders handed to the system name no event.
To turn the lock off, turn off App lock in Settings › Privacy and security. Reset all settings does not turn it off.
Every protection
At the top of Settings › Privacy and security, a summary says how many of its seven protections are on, such as 5 of 7 protections are on, with a mark for each. Turn on all turns on the rest at once and says which it changed.
The seven are the switches in that section: Load images from the web and Offer to send read receipts; Remove link tracking, Show where a link goes first and Warn about fake senders; and Hide mail in the background and Unlock before erasing or exporting. The count at the top changes as you set each one.
As Nixt Mail ships, two are off: a link opens on the press, and mail stays in view when another window is in front. Nothing becomes a mode: each one stays an ordinary setting with Put back. The App lock is not counted, because it needs a device that can authenticate. Sender logos, Recent searches and Notification previews are settings of the message list and of notifications, and are set there.
Clearing what is kept
Each thing Nixt Mail keeps is cleared where it is set:
| Setting | What it clears |
|---|---|
| Message list › Recent searches | Clear all forgets the searches kept and keeps remembering new ones; turning the switch off forgets them and stops. |
| Message list › Sender logos | Clear the logos kept, while it is on; turning it off deletes them too. |
| Sync and offline › Mail kept for offline reading | Clear deletes the encrypted copy of mail on this computer. Your mail on the server is untouched, and the folders you chose fill again as you read. It is greyed when nothing is kept. |
Each clears in place and says Cleared. To remove everything at once, use Erase everything on this device.
Secure storage
When this device will not keep your sign-ins, Settings › Accounts says so under your accounts: Secure storage — Not saving or Secure storage — Saved but unreadable, with what it means. While it works, nothing is shown. See Staying signed in.
Certificates you trusted
When you connect to a server with a certificate your computer does not trust, Nixt Mail shows you its fingerprint and asks. If you choose Trust and connect, Nixt Mail remembers that exact certificate for that account, and refuses to connect if the server later presents a different one. See Certificates.
Links and phishing
Nixt Mail points out links whose text names one place but that go to another, and only opens web and email links. To see every link’s real address before it opens, turn on Settings › Privacy and security › Show where a link goes first. See Links.
Attachments that are programs
Program files attached to mail — such as .exe, .bat, .sh, .dmg, .pkg or .jar — are saved when you click them but never opened. See Attachments.
Erase everything on this device
Erasing removes every account, saved sign-in, setting and piece of kept data Nixt Mail has put on this device. Your mail itself is untouched: it stays on your provider’s servers.
- Open Settings › Privacy and security.
- At the end, under Start over on this device, choose Erase everything on this device.
- Read the dialog Erase everything on this device? — Nixt Mail will forget your accounts, passwords, settings, calendar on this device and any mail kept for offline reading on this computer. Your mail itself is untouched — it stays on your provider’s servers. This cannot be undone.
- Choose Erase, or Cancel.
The button reads Erasing… while it works. When it finishes, a snack bar says Everything Nixt Mail stored on this device has been erased. and Settings closes. First-run setup appears again the next time you open Nixt Mail.
Erasing also destroys the keys that encrypt offline mail and the calendar on this device, so nothing left behind can be read.
Reset settings without erasing
To put your choices back to their defaults while keeping your accounts, signatures, rules and mail, use Reset all settings in Settings › General. See Restore defaults.
Related
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