> For the complete documentation index, see [llms.txt](https://doc.batch.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.batch.com/guides-and-best-practices/email-deliverability/email-authentication-and-sending-structure/sending-subdomain-setup-and-troubleshooting.md).

# Sending Subdomain Setup & Troubleshooting

- [Sending Subdomain Architecture](https://doc.batch.com/guides-and-best-practices/email-deliverability/email-authentication-and-sending-structure/sending-subdomain-setup-and-troubleshooting/sending-subdomain-architecture.md): Learn how to segment your email traffic across multiple subdomains  to isolate risk and optimize your sender reputation.
- [Setting Up a Sending Subdomain](https://doc.batch.com/guides-and-best-practices/email-deliverability/email-authentication-and-sending-structure/sending-subdomain-setup-and-troubleshooting/setting-up-a-sending-subdomain.md): Get to know how to set up a new sending subdomain with Batch to send your first emails.
- [Troubleshooting Email Authentication Issues](https://doc.batch.com/guides-and-best-practices/email-deliverability/email-authentication-and-sending-structure/sending-subdomain-setup-and-troubleshooting/troubleshooting-email-authentication-issues.md): You will find here all the information you need to troubleshoot issues with SPF, DKIM and DMARC.


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