I sent 2,000 cold emails in a month. Got 3 replies, 0 demos, and my domain got blacklisted.

I’m a technical founder. I can build a product, fix a database, and debug an API in my sleep. But sales? I hate it.

We needed revenue, so I decided to try cold emailing. I bought a list of 2,000 leads from a B2B database, wrote a 4-paragraph email explaining our features, and set up a sequence to send them out from our main company domain. I figured if I hit enough inboxes, someone would eventually buy.

I was wrong. Here is the exact result after 30 days:

• 2,000 emails sent.

• 3 replies (two of which were "unsubscribe," and one was an angry person telling me to stop spamming).

• 0 demos booked.

• And the worst part: Our main domain got flagged by Google, so now all my transactional emails (password resets, receipts) are going to spam.

I completely destroyed our domain reputation because I didn't warm up the email, didn't use a secondary domain, and sent generic emails pitching features instead of personalizing the pain points. I was acting like a spammer because I didn't know what else to do. Now I have to spend weeks fixing our email deliverability just so our actual users can log in again.

For founders who actually cracked cold outreach: What is the bare minimum setup you need before sending your first cold email?

Do you have to use separate domains? Do you hire an agency just for the technical setup? How do you personalize at scale without spending 5 hours on each email?