Salesforce Marketing Cloud's Custom List Detective (CLD) helps prevent sending to invalid, role-based, or spam-likely addresses, blocking both commercial and transactional emails. It can block specific domains and usernames, aiding deliverability. However, it's not fully effective against sophisticated bot signups, and third-party email validation services are often recommended as a more robust alternative. CLD incurs costs based on lookups, and requires proper configuration, regular rule updates, and monitoring to maximize effectiveness. Integrating CLD with other email marketing tools is recommended. There was a past UI bug, and maintaining overall email data quality remains crucial.

Experts and email marketers generally agree that Salesforce Marketing Cloud's Custom List Detective (CLD) provides a basic level of email hygiene by blocking specific domains and usernames. However, it's not fully effective against sophisticated bot signups. Many suggest considering third-party email validation services for more comprehensive hygiene. CLD can incur additional costs, and users should regularly review and update its rules. Integrating CLD with other email marketing tools, monitoring its impact, and leveraging its reporting features are also considered best practices. A past UI bug where 'allow' entries could inadvertently block addresses should be considered.

Experts indicate that Salesforce Marketing Cloud's Custom List Detective (CLD) blocks both commercial and transactional messages. It can block specific domains and usernames but is not effective against bot signups using techniques like drip dots. A past UI bug caused 'allow' entries to block instead. Maintaining overall email data quality is crucial for deliverability; CLD is helpful but not a replacement for comprehensive data management.

Salesforce documentation describes Custom List Detective (CLD) as a tool to prevent sending to invalid, role-based, or spam-likely addresses, thus improving deliverability and protecting sender reputation. It blocks both commercial and transactional emails. Proper configuration is essential for maximizing effectiveness and minimizing false positives. However, CLD has limitations and requires ongoing maintenance to address evolving spam tactics; it is not a comprehensive solution for all email threats.