Cold Emailing
CEO and co-founder
How to Connect Infraforge to Smartlead: Complete Integration Guide
Updated March 2, 2026
TL;DR: Connecting Infraforge to Smartlead requires exporting SMTP/IMAP credentials and formatting a CSV with headers
password,smtp_host,smtp_port,imap_host, andimap_port. Use port 587 for SMTP (TLS) and 993 for IMAP (SSL). The manual process requires careful attention to CSV formatting, while Inframail's native Smartlead integration exports pre-formatted files ready for one-click import at $129/mo flat rate for unlimited inboxes.
You have the infrastructure (Infraforge) and the sender (Smartlead), but the bridge between them is where most agencies lose hours. One wrong column header in your CSV export can fail a 50-inbox upload and send you hunting through error messages.
This guide covers the exact workflow to connect Infraforge to Smartlead, including the precise CSV schema, SMTP port configurations, and troubleshooting steps for common authentication errors. I also explain why agencies scaling past 50 domains switch to platforms with native integrations that eliminate manual CSV work entirely.
Prerequisites: Preparing your Infraforge domains for Smartlead
Before exporting credentials, verify that your Infraforge domains are fully configured and propagated. Skipped DNS verification is the most common reason campaigns fail to send on day one.
DNS verification checklist
You must configure three DNS TXT records before connecting to any sending platform. Add SPF, DKIM, and DMARC records to authorize your sending services and ensure emails land in the inbox, as explained in Instantly's deliverability guide.
Required DNS records:
SPF record: Authorizes your sending servers with a TXT record like
v=spf1 include:... ~all. Keep total DNS lookups at or below 10 per RFC 7208.DKIM record: Publishes your public key as a TXT record at
selector._domainkey.yourdomain.com.DMARC record: Specifies what happens when authentication conditions aren't met. Wait 48 hours after adding SPF and DKIM before adding DMARC.
Gmail's bulk sender rules (effective February 2024) require SPF, DKIM, and a DMARC policy of p=none or stricter, plus spam rates under 0.3%.
Pre-integration readiness check
Item | Status Required | How to Verify |
|---|---|---|
SPF record | Propagated (24-48 hrs) | Check with MXToolbox SPF lookup |
DKIM record | Published and active | Query DNS TXT records |
DMARC policy | Set to p=none minimum | Query TXT _dmarc.yourdomain.com |
Master inbox forwarding | Active | Test with manual email |
Domain age | 14+ days recommended | Check WHOIS |
You'll understand why email infrastructure matters when you see how DNS foundations directly impact inbox placement. When you run campaigns on cold email platforms without proper DNS configuration, deliverability often tanks within the first week.
Step 1: Exporting SMTP and IMAP credentials from Infraforge
With DNS verified, you can now export the credentials Smartlead needs to connect to your Infraforge inboxes.
Locating the export function
Navigate to your Infraforge dashboard and locate the inbox management section. The credential export view shows all active mailboxes with the six data points Smartlead needs.
Required credential fields
Based on Smartlead's bulk import guide, you must capture these fields:
Field | Description | Typical Value |
|---|---|---|
Full email address | john@yourdomain.com | |
password | Account password | Your generated password |
smtp_host | SMTP server hostname | mail.yourdomain.com |
smtp_port | SMTP port number | 587 (TLS) or 465 (SSL) |
imap_host | IMAP server hostname | mail.yourdomain.com |
imap_port | IMAP port number | 993 (SSL/TLS) |
Port configuration matters: Use port 587 for SMTP because it begins with a standard connection then upgrades to encryption using STARTTLS, making it the most common choice for cold email infrastructure. Port 465 uses SSL/TLS from the start, while port 993 handles IMAP with SSL/TLS.
Private infrastructure with dedicated IPs gives you better sender reputation management, more consistent inbox placement, and isolation from other senders' behavior. This is why agencies choose dedicated infrastructure providers over shared hosting solutions.
For deeper understanding of these technical terms, our cold email glossary covers 25+ essential definitions for agency founders.
Step 2: Formatting the CSV file for Smartlead bulk import
This step causes the most failures. One misnamed column header or mismatched port number can reject your entire upload.
Exact CSV column headers
Smartlead's bulk import help article provides a sample CSV template that must be followed precisely. After upload, you receive immediate feedback on invalid details like missing passwords or incorrect warmup settings.
Required column structure:
CSV mapping table
Smartlead Field | Infraforge Data | Format Notes |
|---|---|---|
Full inbox address | Include complete domain | |
password | Account password | No special character restrictions |
smtp_host | SMTP server hostname | Usually mail.yourdomain.com |
smtp_port | 587 or 465 | Match with encryption type |
imap_host | IMAP server hostname | Often same as SMTP host |
imap_port | 993 | SSL/TLS required |
Critical formatting rules
No empty cells: Every row must have all six fields populated
Consistent port numbers: Don't mix 465 and 587 unless your configuration requires it
UTF-8 encoding: Save as CSV UTF-8 to avoid character encoding issues
Lowercase headers: Use headers exactly as shown
To see how AI assistance can speed this process, one agency founder demonstrated cold email system setup in under 10 minutes compared to hours of manual configuration.
For agencies managing email warmup migrations, knowing how to properly structure these files becomes essential.
Step 3: Configuring custom domain tracking and warmup
After uploading credentials, configure tracking domains and enable warmup to protect deliverability during the initial sending period.
Setting up custom tracking domains
Open/click tracking requires a CNAME record pointing to Smartlead's tracking servers. According to Smartlead's tracking domain guide:
Open your domain management tool (GoDaddy, Namecheap, Cloudflare)
Navigate to the DNS management section
Add a CNAME record with these settings:
Type: CNAME Record
Host: emailtracking
Value: open.sleadtrack.com
TTL: Automatic
In Smartlead, paste the full URL:
http://emailtracking.yourdomain.comClick "Verify CNAME"
DNS changes take 2-4 hours to propagate. If verification fails immediately, wait before retrying.
Warmup configuration
Enable warmup in Smartlead for each imported inbox before launching campaigns. The best warmup settings video covers optimal configurations that apply to Smartlead's warmup system. Smartlead recommends at least 2 weeks of warmup before full campaign volume.
Monitor metrics during warmup using Inframail's spam detection guide.
Common integration errors and how to fix them
Based on Smartlead's bulk import documentation, the platform provides immediate feedback on CSV issues. Here are the most frequent problems and solutions.
Error 1: Authentication failed (535)
Cause: Wrong password, incorrect port, or authentication not enabled on the server.
Fix:
Verify password matches exactly (case-sensitive)
Confirm port 587 with TLS or port 465 with SSL
Check that SMTP authentication is enabled in your infrastructure settings
Error 2: IMAP connection refused
Cause: SSL settings mismatch or firewall blocking port 993.
Fix:
Ensure IMAP port is 993 with SSL/TLS enabled
Verify no firewall rules blocking the connection
Test IMAP connection manually using a mail client
Error 3: Bulk upload validation fails
Cause: CSV formatting issues or missing required fields.
Fix:
Download Smartlead's sample CSV and match headers exactly
Remove any extra columns or blank rows
Ensure no UTF-8 encoding issues from Excel exports
Error 4: Deliverability drops post-connection
Cause: You skipped warmup or your DNS records don't align with Smartlead's tracking domains.
Fix:
Verify SPF, DKIM, and DMARC using Mail-Tester (target 9+/10)
Enable warmup immediately after import
Review healthy metrics within first week
The full cold email setup strategy video demonstrates how to avoid these common pitfalls when connecting infrastructure to sending platforms.
The efficiency gap: Why agencies move to Inframail
The manual process works, but you spend significant time on CSV formatting and troubleshooting, and one error wastes hours. This workflow comparison shows the gap.
Manual CSV process vs. native integration
Task | Manual (Infraforge) | Automated (Inframail) |
|---|---|---|
Export credentials | Manual export | 30 seconds |
Format CSV | Manual formatting | Pre-formatted export |
Upload and verify | Manual validation | One-click import |
Troubleshoot errors | Variable | Pre-validated format |
Inframail exports to Smartlead seamlessly, setting up all records automatically and providing pre-formatted CSV files ready for immediate upload.
"I personally have over 1,000 email accounts with Inframail for one flat price. Adding all those records would have probably taken dozens of hours. Instead all records were added within 10 minutes." - Verified user review of Inframail
Automated provisioning deploys domains and mailboxes with DNS configured automatically across dedicated IPs. You skip manual record entry, DNS propagation waiting, and CSV formatting entirely. Explore what email platforms work with Inframail for full integration options.
Cost comparison: Infraforge vs. Inframail at scale
You save time with automated workflows, but cost math seals the decision when you're protecting 15-20% net margins.
TCO analysis at 50, 100, and 200 inboxes
Google Workspace pricing runs $7.00 per user/month on annual plans or $8.40/month on flexible plans after 2025 price increases that bundled Gemini AI features.
Provider | 50 Inboxes | 100 Inboxes | 200 Inboxes |
|---|---|---|---|
Google Workspace | $350-420/mo | $700-840/mo | $1,400-1,680/mo |
Inframail (flat rate) | $129/mo | $129/mo | $129/mo |
Monthly savings | $221-291 | $571-711 | $1,271-1,551 |
"Unlimited inboxes on a flat price? That alone saves me hundreds every month compared to Google Workspace or similar." - Verified user review of Inframail
Inframail's Unlimited Plan includes 1 dedicated US IP, while the Agency Pack ($327/mo) provides 3 dedicated IPs. Your sending behavior alone determines ESP trust with dedicated IPs, isolating you from reputation damage caused by other senders.
Integration checklist
Use this checklist before starting any Smartlead integration:
DNS preparation:
SPF record propagated (verify with MXToolbox)
DKIM record published at selector._domainkey.domain.com
DMARC policy set (p=none minimum)
Domain age 14+ days
Credential export:
SMTP host captured
SMTP port noted (587 or 465)
IMAP host captured
IMAP port confirmed (993)
Passwords verified
CSV formatting:
Headers match Smartlead template exactly
All six columns populated
No blank rows or extra columns
Saved as UTF-8 CSV
Post-upload:
Warmup enabled for all inboxes
Custom tracking domain configured
CNAME verified in Smartlead
Initial test send completed
Get started with automated infrastructure
The manual Infraforge-to-Smartlead workflow functions, but it requires careful CSV formatting and leaves room for errors that delay campaigns. Agencies scaling past 50 domains find that infrastructure friction compounds into hours of lost time monthly.
Inframail eliminates that friction. You get automated DNS configuration, pre-formatted exports for Smartlead, dedicated IP infrastructure, and flat-rate pricing at $129/mo for unlimited inboxes.
"I can set-up inboxes in 5mins while saving money on Google Workspace subscriptions and benefit from great deliverability. All of my campaigns on Inframail are on a >10% reply rate." - Verified user review of Inframail
Sign up to Inframail and get started today.
FAQ
What is the SMTP port for private email infrastructure?
Standard SMTP ports are 587 (TLS/STARTTLS) or 465 (SSL). Port 587 is most commonly used for cold email because it starts with a standard connection then upgrades to encryption.
Can I use Smartlead warmup with private infrastructure?
Yes. After importing credentials via CSV, enable warmup in Smartlead's inbox settings. Smartlead recommends at least 2 weeks of warmup before full campaign volume.
How does flat-rate pricing compare to per-inbox costs?
Inframail charges $129/mo for unlimited inboxes on the Unlimited Plan, saving agencies $6,000-8,000+ annually at 100 inbox scale versus Google Workspace at $7-8.40 per user/month.
What CSV format does Smartlead require?
Smartlead requires six columns: email, password, smtp_host, smtp_port, imap_host, imap_port. Download their sample CSV template and match headers exactly to avoid upload failures.
How long does DNS propagation take?
SPF and DKIM records typically propagate within 24-48 hours. Wait the full 48 hours before adding DMARC records, and verify propagation using MXToolbox before attempting integration.
Key terms glossary
Private Cold Email Infrastructure: A high-performance platform providing dedicated IP addresses for complete control over sending environment, enabling better sender reputation management and reduced risk from other senders' behavior.
Dedicated IPs: Private IP addresses assigned to individual users rather than shared pools. Your sending behavior alone determines ESP trust, isolating you from reputation damage caused by other users.
Automated Provisioning: Deployment of domains and mailboxes with DNS records configured automatically across dedicated IPs. Eliminates manual record entry and reduces setup time from hours to minutes.
Sender Reputation: The trust score inbox providers assign based on technical authentication (SPF/DKIM/DMARC), spam complaint rates, and sending consistency. Determines whether emails land in inbox or spam.
Deliverability Controls: Technical configurations including DNS records, warmup schedules, and sending limits that influence inbox placement rates across Gmail, Outlook, and other providers.
Social Proof
Inframail now has 38 5-star reviews on Trustpilot (https://www.trustpilot.com/review/inframail.io).
