Outage in SMTP2GO
Delivery delays to Microsoft-hosted recipients
Resolved MinorIncident Report
Some customers sending to Microsoft-hosted recipients may see delays with email delivery due to an ongoing issue from their side, which they are currently working to resolve. Affected emails will have the event status of "Processed" and "421 4.3.2 The maximum number of concurrent connections per resource forest has exceeded a limit, closing transmission channel" events when viewing the email's Timeline, instead of normal delivery events. We continue to attempt delivery of these emails. For more details, 365 Admin users can go here: https://admin.cloud.microsoft/?#/servicehealth/:/alerts/EX1079935
Components affected
SMTP2GO Email sending (SMTP service)Trusted by 1,000+ teams
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Latest Updates ( sorted recent to last )
RESOLVED
11 months ago - at 05/22/2025 09:44AM
This incident has been resolved.
IDENTIFIED
11 months ago - at 05/22/2025 06:41AM
Some customers sending to Microsoft-hosted recipients may see delays with email delivery due to an ongoing issue from their side, which they are currently working to resolve. Affected emails will have the event status of "Processed" and "421 4.3.2 The maximum number of concurrent connections per resource forest has exceeded a limit, closing transmission channel" events when viewing the email's Timeline, instead of normal delivery events. We continue to attempt delivery of these emails. For more details, 365 Admin users can go here: https://admin.cloud.microsoft/?#/servicehealth/:/alerts/EX1079935
Latest SMTP2GO outages
Email Delivery Delays - AU Region - about 1 hour ago
Inbound Server Issue - 15 days ago
Investigating Email Processing Delays (AU Region) - 29 days ago
Network Connectivity Issues - about 2 months ago
Delays sending to Microsoft-hosted domains - 2 months ago
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