Email infrastructure
Email is my strongest specialty. I run my own Postal, MailWizz and mail servers, so the problems I fix for clients are ones I've already had to solve on my own infrastructure.
Services
Installation, connecting them through the API, bounce webhooks, multiple sending domains, and rebuilding a setup after a server loss.
Docker-based platforms: upgrades, domain changes, resets and repairs.
SPF, DKIM and DMARC, rDNS and forward-confirmed rDNS, HELO hostnames, and moving to a new IP range without losing reputation.
Finding why mail is rejected, getting delisted, and dealing with provider-specific blocks and blocked port 25.
Planning warm-up for new domains and IPs, mailboxes for warm-up on your own server, and separating marketing mail on a subdomain.
SMTP relays, Mail-in-a-Box and Mailcow, and sending from devices and apps that need to send mail.
From my own servers
Receivers check SPF for the HELO hostname and for the MAIL FROM domain separately. A correct record for your domain doesn't help if the HELO hostname fails.
Mail-in-a-Box publishes v=spf1 -all for hostnames that have no TXT record of their own, which can make the HELO check hard-fail.
Connect MailWizz to Postal through the API credential, not SMTP, if you want bounces and events to flow back properly.
Some provider blocks, like Microsoft's S3140, don't appear in MXToolbox. You see them only in the rejection message.
Straight talk
Inbox placement depends on your list, content, sending volume and history as much as on the server. I make sure the infrastructure isn't the reason you land in spam: correct authentication, clean IPs, proper bounce handling and a sensible warm-up. Anyone promising a fixed inbox percentage is guessing.
How it works
DNS records, authentication, rDNS, blocklists and the platform setup, checked against what receivers actually see.
Correct the records and configuration, connect the platform properly and handle bounces.
A gradual ramp-up plan for new domains or IPs, so reputation is built instead of burned.
Real work
My own Postal mail server
Self-hosted bulk email platform
Send me the sending domain and what you're seeing. I'll check DNS, authentication and blocklists and tell you what I find.