Can I use same subdomain in adobe campaign classic and for some other automation tool to send out email ?

Hi @abhinav99 , Short answer: Technically, yes but Long answer No. It doesn't matter if the subdomain is delegated to Adobe or not. It won't be recommended by Adobe or other martech automation (They all will deny it). Please refer to the main reasons below why this is not recommended.

1. Subdomain Ownership and Management

• DNS Configuration: Both tools will require specific DNS settings to validate the subdomain. Configuring one might override or conflict with the other.
• SSL Certificates: Managing SSL certificates for the same subdomain across multiple services can be complex and prone to errors.

2. Email Deliverability and Authentication

• SPF Records: Sender Policy Framework (SPF) records need to include all IP addresses that are allowed to send emails on behalf of your subdomain. Combining records for multiple tools can make this complex and increase the risk of errors.
• DKIM Signatures: Each tool will require DomainKeys Identified Mail (DKIM) signing keys. Using the same subdomain may cause conflicts if both tools try to manage DKIM for the same domain.
• DMARC Policies: Domain-based Message Authentication, Reporting & Conformance (DMARC) policies might get complicated when managing them for multiple services.

3. Brand Consistency and Customer Experience

• Email Branding: Using the same subdomain for different tools might affect the consistency of your branding and customer experience, especially if each tool handles templates and content differently
  
  
• ---While it is technically possible to use the same subdomain for Adobe Campaign Classic and another automation tool, it is not recommended due to potential conflicts and complexities.