> For the complete documentation index, see [llms.txt](https://docs.bird.com/taxi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bird.com/taxi/email-design-systems/custom-email-design-systems/updating-an-existing-custom-email-design-system.md).
# Updating an existing custom Email Design System
In Taxi, you can update an existing Email Design System by uploading or pasting new HTML.
To do this:
1. Head to the Email Design Systems tab
2. Select the Email Design System you want to update
3. Select the Actions dropdown and select Upload/Paste New HTML\
If you do not see this option you will need to contact your account admin to give you permissions
4\. On the next page if you were not the last person to upload this Email Design System you will see a message telling you who it was last uploaded by
5\. Select the Upload a file or Paste HTML tab and select 'Update HTML'
6\. Before confirming you will see any changes since last revision. This will show:
* The names and labels of any modulezones, modules, editables and fields which are in the new upload that were not in the existing template
* The names and labels of any modulezones, modules, editables and fields which are not in the new upload that were in the existing template
* A summary text for any modulezones, modules, editables and fields which either are added or removed from the new upload that were in the existing template
* If a field was deleted that was default version content
---
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