Use UserIssuerSerialNumber
- Policy ID
- L_SMIMEUseIssuerSerialNumber
- Scope
- User Configuration
- Supported on
- At least Windows Server 2008 R2 or Windows 7
- Source
- Microsoft 365 Apps / Office Administrative Templates (version 5568.1000)
- Category
- Microsoft Outlook 2016 › Security › Cryptography
Description
This policy setting determines whether Outlook uses IssuerSerialNumber as the SignerIdentifier, which enables third-party email client software applications to read encrypted Outlook email messages. For more information about Cryptographic Message Syntax, refer to the RFC 5652 specification.
If you enable or do not configure this policy setting, Outlook uses the IssuerSerialNumber as the SignerIdentifier.
If you disable this policy setting, Outlook uses SubjectKeyIdentifier for the SignerIdentifier, which might prevent third-party email client software applications from reading encrypted Outlook email messages.
Registry
UserHKEY_CURRENT_USER
- useissuerserialnumberREG_DWORD