Allowing sessionStorage

ProtonMail uses the latest in web technologies to secure your data, and requires sessionStorage. This article will explain what sessionStorage is and address common issues.

What is sessionStorage?

sessionStorage is a new web technology that lets you store website information securely on your device. We use sessionStorage to store your MailboxPassword which is used to decrypt all messages in your account. Without sessionStorage we would need to ask you for your MailboxPassword every single time you read or send an email. Thanksfully, that’s not the case.

I got an error saying I don’t have sessionStorage. How do I get it?

First, see if your browser supports sessionStorage, a list of supported browsers can be found here.

For All Browsers: 

Please ensure Cookies are Enabled.

  1. Firefox
  • Type in about:config in the address bar and hit enter.
  • Click on the I’ll be careful, I promise button.
  • To Enable DOM Storage, just scroll down and double click on the entry to change the “value” from false to true 

2. Internet Explorer

  • Go to Tools -> Internet Options
  • Click on the Advanced tab, then scroll down to the Security section under Settings.
  • Check the Enable DOM Storage box and click on OK.

3. Chrome

  • Open Options
  • Select the Under the Hood tab and click on Content Settings
  • Select Cookies and set Block sites from setting any data

3. Safari

Disable private browsing mode and use regular browsing mode.

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  1. Ron French

    I can not figure out how to create different storage boxes for each person that I correspond to and need to keep the email for future use. I know Im not being clear but it would normally go under the inbox icon.
    Thank you,

  2. Asma

    I am trying to log into my protonmail inbox but it is not letting me. It keeps taking me to a page that says “click here if you have a problem.” I clicked and I got here to comments. I need to login because I gave this email address to a potential employer whom I am in the middle of an exchange with and this is a crucial time for me to interact.

  3. Steve R

    I am using firefox 40.0.2 and it is loading a blank screen, will protonmail support this version as it was the only option when I recently installed firefox.

  4. KS

    The instructions for enabling sessions and allowing cookies appear to be incorrect (don’t follow the format of Chrome ver 65) and in conflict (ie cant both allow cookies and enable sessions). I may be misunderstanding the instructions, however.

  5. Fix Err Spdy Protocol Error

    There are many more issues while using the Chrome browser. One of the general issues is the error of Err Spdy Protocol. It appears when you are trying to open a new webpage. Last day when I was using the chrome this error appears again and again. Then I visit Fix Err Spdy Protocol Error for the help. I follow all the steps mentioned and now there is no such issue on my system.

  6. Anuki

    Hi, it seems i have maxed out by storage with just 62 emails… This cannot be right?

  7. Anuki

    it’s okay… problem solved! 😉

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