Blog · Topic

#deferrals

2 posts tagged “deferrals”.

Deliverability
Gmail 421 4.7.28 on a new sending domain: variants and how to ramp
Gmail's 421 4.7.28 is a temporary throttle, not a block: it saw an unusual rate from your IP, DKIM, SPF or link domain. Read which one, then ramp volume slowly.
Nov 5, 20264 min read
Deliverability
Yahoo 421 4.7.0 TSS04: why your mail is deferred and what to do
Yahoo's 421 4.7.0 TSS04 is a temporary deferral tied to volume or complaints, not a permanent block. What Yahoo says, what to check, and how to retry safely.
Nov 3, 20264 min read

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