Scheduled emails always get blocked by yahoo and gmail

[JuhaszBalint2]

Hello

I'm on the free tier currently. I'm getting this issue when targeting non gmail email addresses.

Email was deferred due to the following reason(s): [IPs were throttled by recipient server]

Edit: I've noticed the following: Yahoo.com and gmail.com block the scheduled emails ie they almost never get delivered to my gmail and yahoo personal accounts (email addresses). The message is this:

The email was not delivered to the recipient. We'll continue trying to send this email for a few more hours, then show a Bounce if it can't be delivered. Learn more.

Latest response from the yahoo.com server:

Email was deferred due to the following reason(s): [IPs were throttled by recipient server]

However for non-gmail-yahoo-addresses eg. cock.li, they do get sent at the scheduled time but they always end up in Spam folder.

Again, I'm on the free tier. Do I have to buy the subscription for 20 USD a month for this NOT to occur?

[JuhaszBalint2]

Now I've got

421 4.7.32 Your email has been rate limited because the From: header (RFC5322) in this message isn't aligned with either the authenticated SPF or DKIM organizational domain. To learn more about DMARC alignment, visit https://support.google.com/a?p=dmarc-alignment To learn more about Gmail requirements for bulk senders, visit https://support.google.com/a?p=sender-guidelines. 71dfb90a1353d-52c53725d86si1196800e0c.72 - gsmtp

[manisha1997]

https://sendgrid.com/en-us/blog/gmail-yahoo-sender-requirements
Hello!
You can go through this doc to understand the requirements and configure the mail accordingly.

[ggarcia196x]

I put together a Claude Code skill that walks through exactly this:

npx skills add sales-skills/sales --skills sales-sendgrid

Then prompt it with: /sales-sendgrid my scheduled emails are getting blocked by Gmail and Yahoo — I'm getting a DMARC alignment error and IPs are being throttled

It'll walk you through domain authentication (SPF/DKIM via CNAME records), making sure your From address matches the authenticated domain, setting up a DMARC record, and whether you need a dedicated IP for the throttling issue.

For the broader deliverability side (warmup, reputation, inbox placement across providers), there's also:

npx skills add sales-skills/sales --skills sales-deliverability

Source: https://github.com/sales-skills/sales