Build error for "acme.auth.eab.hmac-key": Failed to base64 decode HMAC key

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My domain is: thewilliamsgang.com /mail.thewilliamsgang.com

I ran this command: I was attempting to configure the ACME provider in Stalwart email server.

It produced this output: Failed to reload settings * Build error for "acme.auth.eab.hmac-key": Failed to base64 decode HMAC key

My web server is (include version): Stalwart email server 3.8 (I think)

The operating system my web server runs on is (include version): Coolify / Docker /Linux

My hosting provider, if applicable, is: Hostinger

I can login to a root shell on my machine (yes or no, or I don't know): Yes

I'm using a control panel to manage my site (no, or provide the name and version of the control panel): Coolify

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):

I somewhat understand why this happened and I was able to get it to work. The EAB ( External Account Binding) are often one time use. I THINK I was attempting to use a previous one and that was giving the error. I removed the Key ID and the HMAC Key when I re-submitted the form and it worked correctly. Figured I would leave this out here just in case someone in the future has a simialr problem. I knewif I posted something, then I would find the answer. lol

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No part of the problem was that Let's Encrypt does not use EAB credentials, but also EAB keys are encoded in a specific format (base64) and you were probably providing a credential meant for something else like a user account, Let's Encrypt didn't give you any EAB credentials.

EAB is for things like when you already have an online (paid or free) account with a CAs, to link up your ACME client account with that customer account etc.

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