Firefox: Microsoft live.com login error (OCSP certificate issue)

[German]Currently Firefox users are facing login issues with Microsoft live.com services (Hotmail, Outlook, OneDrive). It's not possible to authenticate at live.com. Here are a few details.

A reader of my German blog informed me this morning about the login issue. I wasn't aware of this, because I don't login frequently to live.com, and I use Google Chrome.

SEC_ERROR_OCSP_INVALID_SIGNING_CERT

Accessing Hotmail, Outlook, OneDrive or other Microsoft online services, a user need to login to live.com. In Google Chrome or in Internet Explorer I receive the login form as shown below.

But Firefox (I've tested it with version 53.0.3) drops the following error page after entering the URL live.com:

Secure Connection Failed

An error occurred during a connection to outlook.live.com. Invalid OCSP signing certificate in OCSP response. Error code: SEC_ERROR_OCSP_INVALID_SIGNING_CERT

The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.

Please contact the website owners to inform them of this problem.

Here is my German login site.

The login form isn't displayed, so an authentication isn't possible. It seems, there is an certificate issue in Firefox. Searching the Internet showed me, that this live.com issue seems to exists since a few hours. In Microsoft Answers this thread addresses this issue and also Mozilla has this older article, dealing with OCSP. OCSP is an extended security features in Firefox. The certificate error need to be corrected from web site vendor.

A workaround

But there is a workaround, helping Firefox users to login to Microsoft live.com. Just disable OCSP check within the browser.

1. Enter about:config ein into the browser's address bar and confirm the warning.

2. Search for the option security.ssl.enable_ocsp_stapling, double-click it and change its value to false.

After changing this option to false, the live.com login form should be shown also in Firefox. This issue should also work with other login sites. After the issue has been resolved from Microsoft, repeat the above steps and enable the option again. So check after a while, whether the issue has been resolved.

Addendum: Certificate expired

Paul v Brouwershaven has pointed me to the right direkt direction with this tweet.

@etguenni https://t.co/HzSHmJiZgI pic.twitter.com/3aLF1qiO8r

— Paul v Brouwershaven (@vanbroup) 29. Mai 2017

This web site,  shows the certificate status, which is expired on May 28, 2017. The update will be tomorrow May 30, 2017. Another workaround is, using direkt login with hotmail.com, outlook.com and so on. Strange thing …