Lesson 7: Email warm-up and infrastructure

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In this lesson, you’ll discover warm-up and infrastructure planning – two key pillars for stable lead flow and predictable revenue from cold email. You’ll learn how warm-up evolved from manual email exchanges with friends, to community-based networks, and eventually to fully automated systems built into cold email tools.

We’ll also explain why platforms like Woodpecker are now able to offer warm-up again through external partnerships and what that means for you as a sender. Finally, we’ll talk transparently about the current landscape: whether Google actively penalizes automated warm-up, the risks involved, and why infrastructure planning is more important than ever.

In this lesson, you’ll learn:

• How email warm-up evolved from manually emailing friends, to community-driven networks, to fully automated systems and why each stage emerged as a practical solution to the same core problem of building sender reputation with email providers
• Why Google intervened in 2023 to ban fully automated warm-up, forcing sequencers like Woodpecker to choose between keeping OAuth2 access and offering warm-up and how that trade-off was resolved through external provider partnerships
• That for Google accounts specifically, automated warm-up now exists in a grey area and that Woodpecker is being transparent about that uncertainty so you can make an informed decision rather than being caught off guard
• Why warm-up still matters enormously for inbox placement, and why the alternatives at scale are limited – something the next lessons will walk you through in detail so you can plan your infrastructure with confidence

Hi, following this lesson we will have a series of lessons on warm-up and infrastructure planning.

Investing time into planning this out is very important.

Being in control of your infrastructure will give you stability in your lead flow.

A stable leadflow will result in stable and more predictable revenue from cold emailing.

Let’s start with the concept of warm-up.

Warm-up has had a turbulent history and it all started with a manual approach. 

People used to send some emails to their friends and colleagues and ask them to reply.

These positive interactions told the email service providers that your emails are actually wanted. 

Seeing this the email service provider would then trust you more and improve your reputation.

Better reputation = better inbox placement.

A few years later warm-up evolved into a community driven network. 

Systems were created where cold email senders could help each other to warm-up their accounts.

You didn’t have to annoy your friends and family anymore with tons of warm-up emails anymore.

This worked for a while but also relied on the fact that everyone contributed equally.

Further it was still a manual process and quite time consuming.

The next step in the warm-up evolution were systems that worked fully automated.

Cold email sequencers started to provide networks of email addresses that you could join. 

Any email account in that network was automatically sending, receiving, opening, and replying, etc. Basically emulating normal and healthy email conversations at scale. 

Sounds perfect right for the cold emailer? It was…. until it wasnt… and Google stepped in.

In 2023 Google announced that you are not allowed to use any sort of fully automated warm-up. Additionally, they contacted any providers of such services to stop them immediately. 

That’s why, for instance, GMass shut down. 

Services that did not comply would not be able to go through Google’s audit.

Without the audit you are not able to use OAuth2 to connect their email accounts. 

OAuth2 allows you to use Google’s own authentication window to connect an email account.

Typically such connection is easier, quicker, and less prone to disconnects.

To keep OAuth 2 for our users we decided to stop offering warm-up for Google email accounts

Now you may be wondering why Woodpecker now offers warm-up again. 

Well, most sequencers that went through Google’s audit have partnered with external providers.

This way we can offer stable email account connections and still offer warm-up for Google accounts.

Now for full transparency we do not know if Google actively monitors warm-up and penalizes it.

In the end you have to decide if you want to use automated warm-up for Google email accounts or not.

However there are not many alternatives at scale and I will explain to you why in the next lessons. 

See you there.