Microsoft KB Archive Search

Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

  1. Home
  2. Can't send S/MIME encrypted mail or update the S/MIME control from Outlook on the web in Exchange Server 2016

Can't send S/MIME encrypted mail or update the S/MIME control from Outlook on the web in Exchange Server 2016

View products that this article applies to.

Summary​​​​​​​

This update fixes the following issues that you may experience when you use the S/MIMIE encryption in the Outlook on the web client (previously known as Outlook Web App) in Microsoft Exchange Server 2016:

  • When you access a mailbox that's hosted on a computer by using the Outlook on the web client that has the S/MIME control installed, you may receive the error message "Your S/MIME control is out of date. You must reinstall it." In addition, this issue persists even if you reinstall the S/MIME control.
  • You can't send an S/MIME signed or encrypted email message in the Outlook on the web client. In addition, you may receive the error message "An error occurred while encoding this S/MIME message. An unexpected S/MIME error occurred." especially when you rehydrate a draft, compose the email message for more than a minute, or add attachments or images to the message.

↑ Back to the top

How to get this update

To get this update, install Cumulative Update 11 for Exchange Server 2016 or a later cumulative update for Exchange Server 2016.

After you install the S/MIME control update, when you open the Outlook on the web client in Internet Explorer for the first time, you are prompted with the following message:

Do you want to allow the domain <owa website> to use the S/MIME control to encrypt and decrypt messages in your inbox? Only allow domains that you trust. If you select Yes, you won't be prompted again for this domain. If you select No, the domain won't have access to S/MIME.

When it's shown, click Yes to trust the domain.

↑ Back to the top

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

↑ Back to the top

References

Learn about the terminology that Microsoft uses to describe software updates.

↑ Back to the top

Keywords: An error occurred while encoding this S/MIME message. An unexpected S/MIME error occurred., Your S/MIME control is out of date, Can't send S/MIME encrypted mail or update the S/MIME control, kbexpertiseadvanced, kbqfe, kbsurveynew, kbfix, kb, CI88455, kbContentAuto

↑ Back to the top

Article Info
Article ID : 4459847
Revision : 13
Created on : 7/30/2020
Published on : 7/30/2020
Exists online : False
Views : 298