Can outside users respond to encrypted messages?

Yes, outside users can respond to encrypted messages you send to them. When you send a password encrypted email to an outside user, the recipient will be able to reply in the message view page by clicking “Reply Securely”.

Reply to an encrypted message

The recipient will be able to reply using this editor up to 5 times, after which they will need to create a ProtonMail account.

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  1. Svein Daniel

    How about when sending email to outside users, that they can go to a web page on where they can reply. Where similar technology to how emails within protonmail are encrypted is used, where maybe it is created a temporary user for that particular email or for that particular email address..
    So that when they reply via that web page they got a link to, the email is encrypted on client-side (in browser) and sent.

  2. Anon

    So basically when external user views encrypted email in browser they can respond via a webpage that is inside protonmails secure server and drops it into the protonmail account.

  3. John

    As of today the replying to the encrypt outside mails doesn’t but it works to just read the mails. Only a blank page appears when somebody tries to reply to the message.

  4. Alexander

    John, I’m happy to notify you that replying to secure outside mails works as of today. đŸ™‚

  5. zoran

    I send an encrypted message.
    They reply unencrypted, my message is at the bottom of their unencrypted email. So may original mail is in the clear now. Is that correct?
    If yes, how about not allowing the respondent to reply unencrypted?

  6. Mike

    Why can the external recipient reply only 5 times before they have to sign up? Protonmail is great, but I don’t want to hassle the people I use it with.

  7. Tom

    I agree ^^^^ I’m not going to use this service if its going to force others to join. There are other options out there that don’t do this.

  8. Shirley

    If I encrypt a message sent to a outside user, if they reply unencrypted, does it make my original encrypted message now viewable to anyone who goes through the outsiders e-mails?

  9. ProtonMail Support

    They can only reply encrypted.

  10. Blaque

    What’s the status on that ?
    If it’s still the same, does that mean that an outsider can only securely reply this way AND only 5 times ?
    I get that this is growth-hacking for you, but I don’t expect non-technical persons that I communicate regularly with to sign up to a new email service, with a new email address and 2 passwords just so we can keep having a secure conversation.
    This is borderline LinkedIn behavior, I really expected more from you guys…

  11. ProtonMail Support

    The limit is 5 replies to a message. Every message you send as encrypted to an outside recipient has this limit. This means that the recipient can reply to that message up to 5 times. Every new message you send will again have the limit of 5 replies.

  12. Grim Squeaker

    Clarification request: Is that 5 replies per recipient outside email address per email thread, or 5 replies per recipient outside email address, absolute? If the latter, I agree with a previous poster that this seriously impairs the utility of ProtonMail for most users (myself included). If the objective of this rule is to throttle unplanned demands on the ProtonMail infrastructure, I would request that you offer an option to pay a reasonable fee to waive that restriction for a specific ProtonMail account. If there is a different objective, could you please enlighten us? Thank you.

  13. ProtonMail Support

    The limit is per email message, not per outside address. All messages have limit of 5 replies per thread.

  14. Matty

    Why only five times ? It’s very restricted ….. Did you plain to change this restricted features with the next update ? I think that this thing is fondamental .
    Please let me know , thanks

  15. ProtonMail Support

    That is the limit for now. This limit is for every messages individually. The thread can contain only 5 replies, you can still send a new message that will have 5 replies also.

  16. AF

    I also think the limit of 5 replies is restrictive, and I would pay to have this removed. The limit is hidden – I only found it after I paid up – not that I regret paying you for the service.

    In addition I would like to store the password that I send email to non-pm users with in the contacts list, so that if I send further emails I can automatically use the same password.
    Finding a secure channel to pass the password with is difficult.
    Yes it would be nice if everyone used protonmail, but as others have said we can’t impose this on others, especially the non-technical.

  17. Jurgen

    The limit of 5 replies is too restrictive; from a marketing perspective it would be better to make it 10 or more and add a counter showing the remaining number.

    To pass the password to the recipient an encrypted link that is only available for a certain (sender defined) time would be interesting. By default, the same recipient should keep the same decrypt password, with an option for the recipient to change it.
    This option will solve the problem of having to invent a new PW for every new recipient or e-mail.
    Otherwise people will send the same PW by nonencrypted e-mail to different recipients, where it will remains visible for far too long.

  18. elaynnea

    I find you’re requirement for non PM users to have to signup and create an account after only 5 return emails a bit pushy and a hassle. I know many people that will just say, ‘the heck with all that’ and return my mail via regular unencrypted email services, or maybe not at all. It should be as easy as possible, to get people interested enough to actually try out the program. Not everyone shares my Privacy obsession.

  19. ProtonMail Support

    This is needed for longer conversations. Every new message has the same 5 message count

  20. 22532

    For the password sharing issue, the answer is simple: Use PGP rather than passwords.

  21. Cali

    hes sayings you get 5 replys, then you’ll have to create a fresh email with the person, then another 5, create new email with person.. etc..

  22. Anonymous

    It seems too much of a coincidence that virtually all the comments posted by visitors about his topic misinterpret or cast doubt and confusion about the 5 reply limit by non-proton email users. Several visitors expressed dissatisfaction based on their misunderstandings despite several clarifications by the proton support staff.

    Most of the visitors’ suggests to improve or facilitate email replies by non-proton email users would undermine the whole privacy and security premise behind encryption based email services such as proton email and others.

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