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Important Announcements

Cisco Secure Email Add-Ins No Longer Supported on Microsoft Outlook 2019

This is to inform you that, effective October 14, 2025, Microsoft Outlook 2019 is no longer supported for the Secure Email Encryption Service Add-In and Secure Email Submission Add-In.

To continue using these Add-Ins, we recommend upgrading to Microsoft 365. Starting October 2025, download and install the new manifest for:

- Secure Email Encryption Service Add-In from the CRES Admin Dashboard

- Secure Email Submission Add-In from the Cisco Software Download Portal

After downloading the manifests, follow the instructions provided in the Submission and Encryption Add-In guides. For more information, see: Cisco Email Encryption - End-User Guides.

TLS 1.0/1.1 Deprecation from AsyncOS for Secure Email Gateway, Starting version 16.5

We would like to inform you that starting with the AsyncOS 16.5 release, TLS versions 1.0 and 1.1 will no longer be available as configuration options in both the CLI and GUI.

To ensure secure email delivery and receipt, you should use TLS versions 1.2 and 1.3. These versions can be configured via the sslconfig CLI command or through the System Administration > SSL Configuration menu in the user interface.

For detailed instructions on updating TLS versions, please refer to the “System Administration” section of the User Guide for AsyncOS 16.0.x for Cisco Secure Email Gateway.

 

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Migrate from Secure Email Virtual C100V to Avoid McAfee-Related Issues

  Important: Migrate from Secure Email Virtual C100V Models to Avoid McAfee-Related Issues Dear Valued Customer, We are reaching out to ensure your Cisco Secure Email environment continues to operate at optimal performance and reliability. As worklo...

dmccabej by • Cisco Employee
  • 869 Views
  • 2 replies
  • 0 Helpful votes

Resolved! How to find a message log of IronPort (ESA) by using couple of measures like IP address and email address?

Hi, Greetings!! I would like to find message logs by using couple of measures (IP and email address), can you please suggest. I am able to find email logs with only one measure with particular email address or IP address. For example: Wed Oct 19 18:...

pbabu6001 by • Level 1
  • 7892 Views
  • 5 replies
  • 0 Helpful votes

Resolved! #5.3.4 message header size exceeds limit

Hi !We are getting this bounce error message from our customers trying to send emails to our newly built C370 Ironport box.Here is the error message; "The following message to nilesh.prasad@mitchelkeil.com.fj was undeliverable.The reason for the prob...

IronPort and HTML Email

Hello,We are running into a problem since switching to IronPort email filtering from our Exchange Servers using SMTP.  We have several websites running PHP and using the PHP mail() command to send HTML email directly from applications.  We set the Co...

SMTP Relay for external domain

We are using ESA for internal SMTP relay servers in our domain, now I have a request from the internal server they want to send to external domains my worries is if allowed the servers IP to send to outside it will be acting as open relay so how I ca...

amahmud01 by • Level 1
  • 2690 Views
  • 4 replies
  • 0 Helpful votes

Message splintering

I have a question involving splintering.  We have two groups (clusters) of Ironport gateways.  When an email comes to the first set, if it is to one of our internal domains, then it gets routed by an SMTP route to an MX name that is our internal emai...

Resolved! Rewrite Recipient Domain

Hi I want to rewrite the recipients domain of incoming e-mails and forward them to an external host. I've implemented an incoming content filter rule where some addresses (in a dictionary) have been forwarded to an alt-host (external host). that work...

Resolved! SPF validation & content filter

Hi all, I've configured a content filter looking at the SPF and if the status equals fail the message will be dropped and according to the documentation only the PRA identity result is checked. My concern is that messages got dropped if the MAILFROM ...

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