S/MIME message wasn't decrypted successfully

Products

• Email Security.cloud

Issue/Introduction

You have sent an encrypted message, but the recipient has the error:

The S/MIME message wasn't decrypted successfully. The ASN.1 package couldn't be processed.

The recipient see an error in the Outlook:

Environment

Email Security.cloud

Resolution

This is an Outlook error that the recipient is getting regarding decryption.
Email Security.cloud is not in a position to advise on decryption issues that an external recipient is having, and recommend engaging Microsoft support to see what is going wrong with the decryption on the recipient's side.