Email Templete change logo

Hi Team,

I started customizing my verification email - using SMTP email provider.
One of the things I want to customize is the logo.
When receiving an email, some email clients have this “Download images” button you have to click and no images are presented unless you click it.
One way to bypass this annoyance (in a regular email) is attaching the images you want to display to the email itself (as file attachments) and referencing their source in the html as CID - ex:<img src="“cid:Logo.jpg”">.
Another way is to use inline base64 attachments, but most clients seem to block this apparently…

So, now for the questions.
Can I somehow use attachments in auth0 email templates to make the logo appear in all emails without clicking the “Download images” in the email client?
Is there another way (not attachments) to achieve the same?


I am pretty sure that there is no way to do attachments with the template. Doing attachments would require knowing the content-type header, which looks like:
Content-Type: multipart/mixed; boundary="------------5DCDC8D554E2B9E07145E50F"
And then using that boundary to create a raw body with attachment.
But templates cannot do that.

You can see this page:
where Thunderbird puts forth the justification for doing this behavior. Because it is a privacy issue, I don’t think it is going to be easy to get around. It might be easier to help users adjust the setting for your site.


Just an opinion: If I can play Devil’s Advocate, the user has chosen to not automatically display images. Trying to circumvent that seems contrary to good practices.You may think it annoying that your images aren’t displayed automatically. I would consider it very annoying if someone tried to circumvent my settings like this. In fact, I would terminate any relationship with a service that did this.