# Salesforce: Feature Perf Degradation: Core Service

- Impact (vendor’s label): minor
- Status: resolved
- Started: 2025-12-19 21:00 UTC · Resolved: 2025-12-26 15:49 UTC · Duration: 7 d
- Updates: 3 · Affected components: Core Service, 4 instances
- [Vendor status page: https://status.salesforce.com/incidents/20003570](https://status.salesforce.com/incidents/20003570)
- [Company: Salesforce](https://rewindex.com/company/salesforce.md)

## Timeline of updates

- **update** 2025-12-26 15:34 UTC: We are investigating a feature degradation affecting outbound email delivery for a subset of customers. We identified a specific mail transfer agent (MTA) host that is unable to establish connections to external domains, resulting in timeouts and a high rate of failed delivery retries. After performing health checks, we are trying to remove the impacted host from the active pool while deeper investigation continues. We will provide the next update within 30 minutes, or sooner if additional information becomes available.
- **update** 2025-12-26 15:59 UTC: We’ve conducted targeted diagnostics on the impacted host and identified a high failure rate despite low queue volume, indicating a host-level issue. As an immediate recovery plan, we have initiated a restart of the impacted host to restore normal email processing. We will provide the next update within 30 minutes, or sooner if additional information becomes available.
- **update** 2025-12-26 16:29 UTC: We’ve completed restarts on the mail transfer agent host, which resolved the issues with outbound email delivery as of 15:49 UTC. We will continue to monitor the environment to ensure stability and prevent a recurrence. We will also thoroughly investigate the incident, confirming the technical trigger, the underlying cause, and any preventive action to avoid a repeat in the future. We apologize for any inconvenience this issue may have caused you and your business.


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Canonical: https://rewindex.com/company/salesforce/incidents/20003570 · Markdown: https://rewindex.com/company/salesforce/incidents/20003570.md · JSON: https://rewindex.com/api/v1/companies/salesforce/incidents/20003570 · Generated 2026-10-18T10:29:14.917Z