# Custom Email Design Systems

- [Custom-built Email Design System email client support](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/custom-built-email-design-system-email-client-support.md)
- [Understanding Email Design Systems uploader error messages](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/understanding-email-design-systems-uploader-error-messages.md)
- [Updating an existing custom Email Design System](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/updating-an-existing-custom-email-design-system.md)
- [Uploading a custom Email Design System to Taxi](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/uploading-a-custom-email-design-system-to-taxi.md)
- [Uploading an Email Design System using a zip file](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/uploading-an-email-design-system-using-a-zip-file.md)
- [Using custom fonts in an email](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/using-custom-fonts-in-an-email.md)


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