Proton

Accidentally sending an email too soon or to the wrong person can be nerve-wracking, especially if the message contains sensitive information. Many email platforms offer ways to unsend an email and avoid these common pitfalls. However, these features often come with limitations, such as short cancellation windows or compatibility issues, and the methods vary by platform.

This article explains how various email platforms handle email unsending and the limitations of each method. You’ll also see how Proton Mail’s additional features help you manage emails and keep your data secure.

Is it possible to unsend an email? 

Technically, yes — most of the time. Different email platforms offer ways to unsend messages, but the method and effectiveness can vary.

Delayed-sending mechanism

Some email platforms, such as Proton Mail, Gmail, and Apple Mail, use a delayed-sending mechanism to allow unsending emails:

  • Default timer: Proton Mail’s undo send feature has a 10-second delay enabled by default. You can set it between 0 and 20 seconds, where 0 disables this feature.
  • How it works: When you hit the send button, the email client doesn’t immediately send the message to the recipient’s email server. Instead, it holds the email in a queue for the set delay, showing an “Undo Send” button during this time. In Proton Mail, a “Message sent. Undo” banner appears at the top (web app) or bottom (mobile).
  • Canceling the email: If you click the button for undoing the send, the email client cancels the queued message before it leaves the server. In Proton Mail, the email is reopened in the composer window, allowing you to edit or delete it.
  • Final send: Once the delay time passes, the email is actually sent to the recipient’s server, after which it can’t be recalled since it has left the sender’s control.

Server-side recall mechanism

Microsoft Outlook uses a server-side mechanism that operates differently from delayed-sending platforms for unsending emails. It can send a recall request to the recipient’s server, instructing it to delete the email from the recipient’s inbox if it hasn’t been opened yet.

This recall feature only works when both the sender and recipient use the same Exchange Server or Microsoft 365 environment, which is common within corporations.

Take back sent emails with Proton Mail

Proton Mail offers an “Undo Send” button for quickly correcting mistakes, like typos, forgotten attachments, or accidentally sending an unfinished email, helping you maintain email etiquette by avoiding miscommunication and embarrassment. It’s a particularly useful feature for business users, as errors when writing a professional email can impact client or partner relationships.

In addition to undo send, Proton Mail provides features to manage or limit access to your sent emails. Schedule Send lets you control when an email goes out, giving extra time to decide if it’s worth sending.

You can set expiration dates to automatically delete emails after a specific time, or password-protect emails to ensure only authorized recipients can read them — especially helpful if an email is sent to the wrong person. Read receipts offer confirmation when a recipient has read your email — useful if you’re concerned about a mistakenly sent message.

Our mission is to build an internet where privacy is the default. Proton Mail is just part of an encrypted ecosystem for all your data, including email, passwords, internet connections(new window), cloud storage(new window), calendar, and digital assets.

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