Trend Micro
Trend Micro is a spam filter, block list, and firewall solution for promoted for businesses, headquartered in Tokyo. Mail is routed through mailservers owned by Trend Micro (example: *.trendmicro.com). The recipient is able to manage a lot of delivery settings such as spam policy levels and overrides (allow lists).
5 responses across 2 reply codes
SMTP 550
1 responses
SMTP 554
4 responses
1
Trend Micro blocked this under a send block rule. The recipient admin likely blocked your domain or IP. Ask them to allow it if appropriate.
2
Trend Micro says this recipient is invalid. Treat it as a hard bounce and remove the address.
3
Trend Micro does not allow routing for this domain yet. The recipient admin must allow your domain or IP before delivery will work.
4
Trend Micro blocked this recipient under a recipient block rule. Ask their admin to lift the block if the mail is legitimate.
Response catalog adapted from the MIT-licensed SMTP Field Manual by ActiveCampaign / Postmark.