==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):  1.5.1 PGSQL edition.
- Deployed with iRedMail Easy or the downloadable installer? Downloadable Installer
- Linux/BSD distribution name and version:  Debian 5.10.92-1
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  PGSQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Hello,

According to SoGO's documentation, " When receiving S/MIME signed emails, SOGo automatically extracts the PKCS (Public-Key Cryptography Standard) #7 signature and stores it in the user’s personal address book for the contact associated to the email address of the email’s sender". However, this is not working for me. The system correctly identifies the message as being signed with a valid signature. I have added the sender to my address book. However (a) the S/MIME cert is not appearing in their contact card and (b) consequently I cannot send an encrypted message.

The issue is very similar to the one reported here: https://www.sogo.nu/bugs/view.php?id=5150 . I have tried some of the suggestions noted in that thread but no change.

For SoGO, I am using most of the defaults provided by iRedMail including PGSQL as the auth backend. I am not using LDAP. 

The only potentially relevant error I see in the logs is a line that reads: [ERROR] '<0x0x5604156def70[UIxMailRenderingContext]> found no viewer for MIME type: application/pkcs7-signature'

Any help would be appreciated!