Tag: RFC 3161

Today went through many Media that some apps and components in the recently released Windows 11 no longer work since 01.11.2021 and that the cause for this is a certificate that expired on 31.10.2021. In the meantime Microsoft has pointed out in a blog post and also published a patch for some affected components .

Unfortunately, none of the available sources provided detailed information about what exactly the problem was. So let's get to the bottom of this ourselves.

Continue reading "Cause research: Snipping Tool and other components in Windows 11 no longer usable due to expired certificate"

Below is a description of the options available for executing PowerShell script files, and what is possible by signing them.

Continue reading "Code signing for PowerShell script files"

By default, the Microsoft Certification Authority removes the serial numbers of expired certificates from the revocation lists it issues.

However, there are some exceptions to this.

Continue reading "Treatment of expired certificates when issuing certificate revocation lists"

Assume the following scenario:

• A user has received an email message in the past.
• The message was signed with an S/MIME certificate.
• The sender's signing certificate was issued by a certification authority that is trusted by the recipient.
• Thus, the signature was recognized as valid at the time the message was received.
• The user opens the mail again some time later and finds that the signature is classified as invalid.

Continue reading "Microsoft Outlook: Correctly signed e-mails (S/MIME) are displayed as invalid after the signing certificate expires"