S/MIME generic questions

Anything S/MIME related, not related to KeyTalk
7 articles

Outlook is unable to send an encrypted email to recipients in my company

When sending S/MIME encrypted emails within your company using Outlook, your Outlook will lookup the public key of the recipient(s) in the Global Address List (GAL).As such the administrator of your company must ensure that all company users have their valid S/MIME certificate registered in the comp...

Unable to read or send S/MIME digitally signed and/or encrypted emails using Outlook on the Web (OWA) or Exchange Online (O365)

In order to be able to validate S/MIME digitally signed and/or encrypted emails in Outlook on the Web (OWA) / Exchange Online (Office 365), a Microsoft browser extension is required to be installed, called SMIME Control.Microsoft has phased out support for Internet Explorer as of Q1 2021.This S/MIME...

Used S/MIME certificates are not trusted

When sending or receiving S/MIME digitally signed and/or encrypted emails, these email will only be trusted when their CA trust-chains are trusted.These CA trust-chain trusts must be present on the mail client side when using Windows, Mac or Linux. When using MacMail or Outlook for windows or Mac t...

MacMail cannot verify the digital signature, why??

On April 15th 2021, KeyTalk reported a problem to Apple, whereby under specific circumstances MacMail will not trust a digitally signed and/or encrypted email, when using the preview pane in MacMail.This happens only when: The MacMail is used, mail is viewed in the preview pane, the mail arrives on ...

How to send digitally signed emails using iOS Mail (iPhone/iPad) ?

When you wish to send an S/MIME based encrypted email using iOS Mail, your iPhone or iPad needs to be aware of the S/MIME certificate of the recipients, and you must have a valid S/MIME certificate installed in iOS.You can either manually install an S/MIME certificate on your iOS device, or have it ...

How to send encrypted emails using iOS Mail (iPhone/iPad) ?

When you wish to send an S/MIME based encrypted email using iOS Mail, your iPhone or iPad needs to be aware of the S/MIME certificate of the recipients, and you must have a valid S/MIME certificate installed in iOS.You can either manually install an S/MIME certificate on your iOS device, or have it ...

What's the difference between clear text and opaque digital signing using S/MIME?

When sending S/MIME digitally signed emails, depending on the email client, the sender has the option to activate clear text signing. When not using clear text signing, the default will usually be opaque signing. Opaque signing is also referred to as embedded signing.In Windows Outlook, the option c...