Chart who is sending mail as your domain, from a message-trace export
What this is for. Before you enforce a DMARC policy you have to know every system that sends mail as you. DMARC aggregate reports tell you that from the outside; a message trace from your own mail platform tells you from the inside. Export one (Microsoft 365: Exchange admin centre → Mail flow → Message trace) and chart it here to spot the senders you forgot — see step 0 and step 4 of the guide.
Your file never leaves this page — it is read, parsed and charted entirely
in your browser. Like the rest of Mail Ward, this page loads no third-party code at all:
the charts and the .xlsx reader are hand-written and served from here, so it
works offline. Accepts .csv and .xlsx; the legacy binary
.xls format is not supported — re-save it as either of those.