If you are in Single Password Mode, and you reset your Password, or if you are in Two Password Mode, and you reset your Mailbox Password, you will lose the ability to read your existing emails due to the message encryption that we utilize. This only happens in the case of password reset (when you forget your password), but not when you change your password.
Furthermore, if you are in Two Password Mode and you reset your Login Password OR your Mailbox Password, your account will be changed to Single Password Mode, because this is the new default for ProtonMail. When this happens, you will also be unable to read your previous messages.
However, in certain situations, it is possible to recover your existing emails and decrypt them. This is possible in the following scenarios.
- You were in two password mode, then you reset your login password OR mailbox password, and are now in one password mode. However, you still remember your previous mailbox password.
- You are in one password mode, then you reset your password. However, you still remember your previous password.
In these two scenarios, it is possible to regain access to your existing encrypted messages, by re-activating the encryption keys used to encrypt them.
This can be done under Settings –> Keys
The keys page lists all of the encryption keys which have ever been active on your account. When you reset your Password in Single Password Mode, or when you reset your Mailbox Password in Two Password Mode, a new encryption key is generated, and your previous encryption key is deactivated.
To read your old messages, you will need to reactivate your old key. This is only possible if you remember you previous Password (if you are in single password mode) or Mailbox Password (if you are in two password mode).
Clicking on reactivate will prompt you to enter your current Password (if you are in single password mode) or Login Password (if you are in two password mode).
If this operation successfully completes, you will be able to read your previous emails again!
Note, if you have reset passwords multiple times, you may need to try all of your previous passwords until you find the one that can reactivate your encryption key.