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GUIDE21 min read

Email marketing automation: drip sequences that convert

IMAP vs SMTP, Gmail OAuth, SPF/DKIM/DMARC basics, subject-line A/B math, the four sequence frameworks every business needs, and the deliverability monitoring that keeps your inboxing rate above 95% month after month.

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What you will learn

Four email automation skills

Authentication

SPF, DKIM, DMARC, and Gmail OAuth: what each does and how to set it up correctly.

Drip frameworks

The 4 sequences every business needs (welcome, nurture, re-engagement, win-back).

A/B testing

Subject-line tests that produce statistically meaningful results, not noise.

Deliverability

The metrics to watch weekly and the early warning signs of inbox-rate decline.

What you will need

Email automation success is 30% tooling, 70% authentication and content quality. Get all three lined up before scaling.

  • A CRM Solid workspace (free trial works).
  • A sending domain you control (e.g., yourcompany.com, not @gmail.com personal).
  • DNS access to the sending domain (Cloudflare, Route 53, GoDaddy, etc.).
  • A Gmail Workspace or IMAP-capable mailbox to connect.
  • An opt-in or legitimate-interest-documented contact list.
  • A content brief or rough wording for at least your first 5-touch sequence.

Anti-spam law reminder

Commercial email is governed by CAN-SPAM (US), CASL (Canada), GDPR (EU), KVKK (Turkey), and similar regional laws. Every email must include a physical address, an unsubscribe link that works within 10 business days, and (in most regions) prior consent or a documented legitimate-interest basis. CRM Solid auto-inserts the unsubscribe footer; the consent and address are your responsibility.

Step 1: Pick your email channel: Gmail OAuth, IMAP, or SMTP relay

The three viable choices:

  • Gmail OAuth. Native Google Workspace integration via the official OAuth flow. Best inboxing rate on Gmail recipients (most consumer + many business). Limited to ~500 sends per day per user (Workspace policy). Recommended default for B2B teams under 500 daily volume.
  • IMAP + SMTP. Standard protocols supported by every email provider. Works with Microsoft 365, Fastmail, Zoho, your own mail server, anything. Same per-mailbox volume cap as the provider enforces (M365: ~10,000/day; Fastmail: varies). Use this when Gmail OAuth is not available.
  • SMTP relay (SendGrid, Postmark, Mailgun, AWS SES). Transactional/marketing email service. Best for high-volume nurture, transactional, or shared-IP sending. Requires you to manage domain authentication carefully. Deliverability depends on shared-IP reputation; pick a reputable provider.

CRM Solid supports all three. You can mix: Gmail OAuth for sales-rep-sent outbound, SMTP relay for high-volume newsletters, IMAP for support inbound. Pick the right tool per use case.

Step 2: Connect your mailbox

Gmail OAuth (recommended for Workspace teams)

  1. Go to Accounts > Add email account > Gmail OAuth.
  2. Click Authorize with Google. You will be redirected to Google's consent screen.
  3. Grant the scopes:
    • gmail.send (send outbound).
    • gmail.modify (mark replies as read, label).
    • gmail.readonly (sync inbox for unified-inbox view).
  4. On approval, the mailbox connects. Initial sync of last 90 days of mail takes 2-10 minutes.

IMAP + SMTP (Microsoft 365, others)

  1. Generate an app password in your provider's security settings (do not use your account password directly).
  2. In CRM Solid, go to Accounts > Add email account > IMAP / SMTP.
  3. Fill in:
Microsoft 365 typical settings:
IMAP server: outlook.office365.com
IMAP port:   993
IMAP TLS:    SSL/TLS

SMTP server: smtp.office365.com
SMTP port:   587
SMTP TLS:    STARTTLS

Username: [email protected]
Password: <app password from M365 security>
  1. Click Test connection. Both directions should succeed.
  2. Save. The inbox syncs.

SMTP relay (high-volume)

  1. Set up an account with SendGrid, Postmark, Mailgun, or AWS SES.
  2. In CRM Solid, go to Accounts > Add email account > SMTP relay.
  3. Paste the relay credentials (API key or SMTP user/pass).
  4. Verify the From-address domain is configured at the relay.

Step 3: Set up SPF, DKIM, and DMARC

This is the single highest-leverage step in email deliverability. A mailbox without these three records lands in spam folders for 20-40% of recipients. With them set correctly, inboxing climbs to 95%+ on Gmail and 90%+ on Outlook.

SPF (Sender Policy Framework)

SPF is a TXT record on your domain that lists which servers/IPs are authorized to send email for you. Example for a domain sending via Gmail + SendGrid:

# DNS TXT record
Host:  @  (root of yourcompany.com)
Value: "v=spf1 include:_spf.google.com include:sendgrid.net ~all"

# Reading this:
v=spf1               -> SPF version 1
include:_spf.google  -> trust Google's published sender IPs
include:sendgrid.net -> trust SendGrid's published sender IPs
~all                 -> soft-fail everything else (logged but accepted)

Set -all (hard-fail) only after you have verified no legitimate senders are being blocked.

DKIM (DomainKeys Identified Mail)

DKIM cryptographically signs each outgoing email so the recipient can verify it actually came from you. CRM Solid (and Gmail, SendGrid, etc.) generate a public key you publish in DNS:

# DNS TXT record
Host:  default._domainkey.yourcompany.com
Value: "v=DKIM1; k=rsa; p=MIIBIjANBgkqhki..." (long base64 public key)

# CRM Solid generates this for you under
# Accounts > (mailbox) > Authentication > Generate DKIM

Multiple services can each have their own DKIM record under different selectors. Add one per service.

DMARC (Domain-based Message Authentication)

DMARC tells receiving servers what to do when SPF or DKIM fails. Start with reporting-only (p=none) for 7 days, review reports, then tighten:

# DNS TXT record (start here)
Host:  _dmarc.yourcompany.com
Value: "v=DMARC1; p=none; rua=mailto:[email protected]"

# After 7 days of clean reports, tighten:
Value: "v=DMARC1; p=quarantine; rua=mailto:[email protected]"

# After another 14 days clean:
Value: "v=DMARC1; p=reject; rua=mailto:[email protected]"

CRM Solid auto-monitors DMARC reports if you point rua at a CRM-Solid-provided address; alerts you to any authentication failures.

Step 4: Warm up new sending domains for 14 days

A brand-new sending domain (or new mailbox on an old domain) has no reputation with major mail providers. Send 200 emails from a cold domain on day 1 and they land in spam.

The 14-day warm-up curve:

Day    Daily target  Audience mix
1-3    10-20         Internal team, friends, opted-in nurture list
4-7    30-50         70% opted-in, 30% warm leads
8-10   60-100        Mixed warm + small batch cold
11-14  100-200       Standard production mix
15+    Full ceiling  Whatever your sending plan calls for

CRM Solid's warm-up mode for email accounts enforces this curve automatically. Enable in Settings > Warm-up mode > Email with the 14-day preset.

Step 5: Build a 5-touch outbound sequence

The five-touch outbound framework converts at 8-15% reply rate on a well-targeted warm-to-cold audience.

Touch 1 (Day 0): Opener
Subject: {Quick one for|Question for} {first_name|you}
Body:    1-sentence personalized hook + 1-sentence value prop +
         1-sentence soft question. Total < 60 words.

Touch 2 (Day 3): Nudge
Subject: Re: <same as touch 1>
Body:    "Hey {first_name}, in case my last note got buried..."
         + 1 fresh sentence + same question. Total < 40 words.

Touch 3 (Day 7): Value drop
Subject: {Resource for|Sharing for} {first_name|you}
Body:    Standalone useful resource (case study, benchmark, template).
         No ask. Total < 80 words.

Touch 4 (Day 12): Direct ask
Subject: 15 minutes next week, {first_name}?
Body:    Specific calendar link + 1-sentence outcome ("you'll
         walk away with X"). Total < 50 words.

Touch 5 (Day 20): Breakup
Subject: Closing the loop, {first_name}
Body:    "I'll stop reaching out; if anything changes, my door is
         open." Total < 30 words.

All five with stop-on-reply at the sequence level. The breakup email (touch 5) often produces the highest reply rate per send because it forces a decision; recipients who would have ghosted now reply with a polite "not now" or, surprisingly often, "wait, tell me more."

Step 6: A/B test subject lines

Subject lines are the highest-leverage variable in email. Same body, different subject; open rates can swing 2-3×.

In CRM Solid's sequence editor:

  1. Open touch 1 of your sequence.
  2. Click + Add subject variant.
  3. Write two materially different subjects. Examples:
    • Variant A: "Quick question for {first_name}"
    • Variant B: "Saw your {company} post about {topic}"
  4. Set the split to 50/50.
  5. Set the minimum sample size to 200 per variant before declaring a winner.

After 200+ sends per variant, CRM Solid surfaces:

  • Open rate per variant.
  • Reply rate per variant.
  • Statistical significance (p-value).
  • Recommendation: "Variant B wins by X% open rate, X% reply rate, p < 0.05".

Pause the losing variant. Run the winner to the remaining audience. Run a new test on touch 1 every 30 days; fatigue is real.

Step 7: Test deliverability before scaling

Pre-launch checklist:

  1. Send touch 1 to mail-tester.com using the actual mailbox you will send from. Target score: ≥ 9.5/10. Fix anything flagged (missing alt text, broken links, weak from-name, etc.).
  2. Send touch 1 to a 50-email test cohort spanning Gmail, Outlook, Yahoo, Apple iCloud, and one or two corporate domains.
  3. Check the deliverability report 24 hours later. Targets:
    • Gmail inbox: ≥ 95%
    • Outlook inbox: ≥ 85%
    • Yahoo inbox: ≥ 90%
    • Apple Mail inbox: ≥ 95%
    • Corporate inbox: ≥ 80%
  4. If any are below threshold, fix:
    • Re-check SPF/DKIM/DMARC are propagated (dnschecker.org).
    • Remove URL shorteners; use full URLs.
    • Remove image-only emails; keep ≥ 60% text.
    • Avoid spam-trigger phrases ("free", "limited time", "act now").

Step 8: Monitor deliverability metrics weekly

Open Analytics > Email health every Monday. Watch:

  • Open rate: cold target ≥ 40%, warm ≥ 60%. Sudden drop = subject fatigue or deliverability problem.
  • Reply rate: cold target ≥ 8%, warm ≥ 20%. Drop = template fatigue or audience drift.
  • Bounce rate: hard cap 2%. Anything higher, clean the list immediately.
  • Spam-complaint rate: hard cap 0.1%. Above this, all major providers throttle you within days.
  • Unsubscribe rate: target ≤ 0.5% per send. Above 1% means audience targeting is off.
  • Inboxing rate: overall % landing in inbox vs spam. Target ≥ 95%. CRM Solid surfaces this via seed-list probing.

The four sequence frameworks every business needs

1. Welcome sequence (new signup / new customer)

Day 0:   Welcome + 1 most-useful resource
Day 2:   Quick-start guide (3 things to try first)
Day 5:   Customer success story
Day 9:   Power-user feature you might miss
Day 14:  Check-in + ask for feedback

2. Nurture sequence (engaged but not yet customer)

Weekly:  Curated industry insight + soft product mention
Day 7:   Direct value (template, calculator, benchmark)
Day 14:  Case study from a similar customer
Day 21:  Comparison content (your tool vs alternatives)
Day 30:  Direct invite to demo or trial

3. Re-engagement sequence (gone quiet 60-180 days)

Day 0:   "Still useful?" with one-click opt-in to stay
Day 7:   Curated highlight reel of what changed since they left
Day 14:  Big-win product update they may have missed
Day 30:  Final ping or auto-archive contact as inactive

4. Win-back sequence (churned customer)

Day 0:   "What went wrong" - ask honestly
Day 7:   Share what has changed since they left
Day 14:  Offer (extended trial, discounted return)
Day 30:  Final goodbye + opt-out option

Run all four in parallel against the right segment. CRM Solid's sequence routing automatically picks the right framework based on contact lifecycle stage.

CRM Solid email vs Mailchimp vs ActiveCampaign vs Lemlist

Email automation tools fall into three camps: marketing-blast (Mailchimp), nurture/lifecycle (ActiveCampaign), and outbound-cold (Lemlist). CRM Solid unifies all three with social DMs.

CapabilityCRM SolidRecommendedMailchimpActiveCampaignLemlist
Email types
Outbound cold (drip)
Lifecycle nurture
Bulk marketing newsletter
Transactional
Authentication
Gmail OAuth direct
IMAP + SMTP
SMTP relay support
Cross-channel
Email + Telegram in same flow
Email + X DM in same flow
Email + live chat in same flow

The CRM Solid differentiator: email is one channel inside the same sequence engine that runs Telegram, X, WhatsApp, Instagram, and live chat. The same drip can switch channels based on which the contact responds on.

“We were paying for Mailchimp, Lemlist, AND a CRM. Consolidated into CRM Solid. Email inboxing went from 73% to 96% in the first month because the SPF/DKIM/DMARC defaults were actually correct out of the box. Total cost: 60% less.”
Tobias Eklund
Head of Demand Gen · Sentinel Lab

Email automation FAQ

Eight questions every operator works through in their first month of email automation.

Gmail OAuth if your team uses Google Workspace; it is the simplest, most secure, and supports near-real-time webhooks for inbound. IMAP + SMTP if you use any other provider (Microsoft 365, Fastmail, Zoho, custom). Gmail OAuth is also the only path that survives Google's aggressive anti-spam scoring; an SMTP-relayed Gmail account looks more bot-like to Google.
They are three email-authentication standards that prove an email actually came from your domain. SPF whitelists which IPs can send for you. DKIM cryptographically signs each email. DMARC tells the recipient how to handle failures. Without all three, your inboxing rate drops 20-40% on Gmail and Outlook. Setting them up is a one-time 30-minute job; see Step 3.
Sender-first ("[email protected]") consistently outperforms brand ("[email protected]") for outbound. For nurture and transactional, brand is fine. CRM Solid supports both within the same workspace; you pick per-sequence.
For a warm Gmail or M365 mailbox: 50-100/day comfortable, up to 200 for established 6+ month mailboxes. For new mailboxes: start at 20/day for the first 14 days. SMTP relays with shared IPs (SendGrid, Mailgun, Postmark) handle 1000s/day but recipient reputation depends on your domain, not just the relay.
Five touchpoints is the sweet spot for outbound. Seven for nurture. Twelve for re-engagement and win-back. More than that and reply rates fall off a cliff. Cadence: 3 days, 5 days, 7 days, 14 days for outbound; weekly for nurture; monthly for re-engagement.
4-7 words consistently outperforms long subjects on mobile, where 70% of emails are opened in 2026. Personalization in the subject ("Quick one for [name]") gives a ~5% open rate lift on average. Avoid clickbait; open rate goes up but reply rate craters.
Use mail-tester.com or similar before launching: send to a test address, get a score (target ≥ 9.5/10), fix anything flagged. Then send a 50-email pilot to a clean opt-in list and check inboxing across Gmail, Outlook, Yahoo, and Apple Mail. If inboxing is below 90%, fix authentication or content before scaling.
Cold email works for B2B targeting work email addresses where consent or legitimate-interest applies. Warm DM channels (X, Telegram, Instagram) work better for B2C, creators, and anyone where the recipient has interacted with your social content. Use both: email for the formal first touch, DM for the warm follow-up if they engage.
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