Mailosaur incident

Some customers unable to forward emails

Resolved after 41 minutes, affecting SMTP (25) and SMTP (2525) and 1 more, on August 11, 2025.

monitoring Aug 11, 2025, 10:10 AM UTC

We're aware of an issue affecting some customers who are attempting to send emails to external addresses. As a result of a false-positive inclusion of one of our IP addresses in a blocklist, connections to some mail services are being rejected. The IP in question has since been removed from the list, but it may take several hours for this to propagate to other mail services. We are continuing to monitor this issue and will update when we're comfortable that this has been fully resolved.

Started
Aug 11, 2025, 10:10 AM UTC
Resolved
Aug 11, 2025, 10:52 AM UTC
Duration
41m
Detected by Pingoru
Aug 11, 2025, 10:10 AM UTC

Affected components

SMTP (25)SMTP (2525)SMTP (587)SMTP (25) with STARTTLSSMTP (2525) with STARTTLSSMTP (587) with STARTTLS

Update timeline

  1. monitoring Aug 11, 2025, 10:10 AM UTC

    We're aware of an issue affecting some customers who are attempting to send emails to external addresses. As a result of a false-positive inclusion of one of our IP addresses in a blocklist, connections to some mail services are being rejected. The IP in question has since been removed from the list, but it may take several hours for this to propagate to other mail services. We are continuing to monitor this issue and will update when we're comfortable that this has been fully resolved.

  2. resolved Aug 11, 2025, 10:52 AM UTC

    This incident has been resolved.

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