Koltrix
Guides
Hidden Costs in a Multi-Vendor Email Stack
Mailbox host, sending API, help desk, newsletter tool. Subscriptions are the visible part. What a split email stack costs in time, DNS and lost replies.
5 min read
Blog · Guides · page 3 of 6
Guides
Step-by-step how-tos and migration checklists you can follow from start to finish.
GuidesEmail not received? A systematic debugging order
When a customer says your email never arrived, work the problem in order: your logs, the SMTP response, authentication, filtering, then the recipient.
4 min read
GuidesHow to find anything in a shared mailbox: search techniques
Worked examples of finding old threads in a shared mailbox: search by sender domain, exact phrase, date range, attachment and label, and combine filters well.
4 min read
GuidesEstimating Transactional Email Costs as You Grow
A practical method for forecasting how many transactional emails your product will send per month, and what that volume will cost as your user base grows.
4 min read
GuidesPer-User vs Per-Workspace Email Pricing: Doing the Math
Per-user and per-workspace pricing look similar at three people and diverge fast after that. A worked way to compare the two models for your own team size.
4 min read
GuidesEvery DNS record a sending domain needs, in one table
A reference table of the DNS records a domain that sends email should have: MX, SPF, DKIM, DMARC, MTA-STS, TLS-RPT and BIMI, with syntax for each.
4 min read
GuidesHow to triage an email backlog after time off
A runbook for your first morning back: filter to mail that involves you, read threads newest-first, batch-archive the noise, and reply to the few that matter.
4 min read
GuidesWhat Business Email Really Costs a Five-Person Startup
Mailboxes are only one line on the bill. A framework for adding up what email really costs a five-person startup, including sending, support tools and time.
4 min read
GuidesPublishing a 2048-bit DKIM key when DNS splits strings
A 2048-bit DKIM public key exceeds the 255-character TXT string limit. How string splitting works, provider quirks, and how to verify the result.
4 min read
GuidesHow to Evaluate an Email Tool in a Week-Long Trial
A week is enough to evaluate an email tool if you test the right things in the right order. A day-by-day plan for domains, delivery, team workflow and exit.
4 min read
GuidesHow to pilot AI drafting with a small group first
Run a two-week AI drafting pilot with two or three people: pick categories, rate edits, log failures, set go/no-go criteria, then roll out with a style guide.
4 min read
GuidesQuestions to Ask an Email Vendor About Security and Data
Before you move company email to a new vendor, ask where the data lives, who processes it, and how you get it back out. A question list, with our own answers.
4 min read