Your mail has started landing in spam, or large receivers have begun rejecting it outright. It's almost always the same handful of causes: an SPF record that has drifted past its lookup limit, DKIM signing the wrong selector, reverse DNS that doesn't match the sending name, a DMARC policy left at "none" for two years, or a certificate that expired on the submission port.

I test the whole path — resolve the exchangers and actually connect to each one, check SPF, DKIM, DMARC, MTA-STS, TLS-RPT, BIMI, reverse DNS and twelve major blocklists — then fix what's broken.

I run my own mail infrastructure at DMARC p=reject, and I built the diagnostic tools I use to do this.

Full audit of one domain, written

Every record implemented and verified

Blocklist delisting where needed

A staged path to DMARC p=reject without blackholing legitimate mail