Your sending server could not get a response from the recipient mail server. The remote server may be down, unreachable, or the connection timed out before a response was received.
What Does Error 441 Mean?
SMTP code 441 indicates that the sending server attempted to connect to the recipient's mail server but received no response. This is typically a network-level or server-availability issue rather than a problem with your email content or sender reputation.
Common scenarios include the recipient mail server being temporarily offline for maintenance, network routing issues between the sending and receiving servers, or DNS problems that prevent proper server resolution. This is a transient error and your sending server should retry automatically.
Common Causes
- Recipient mail server is temporarily offline or undergoing maintenance
- Network routing issue between sending and receiving servers
- DNS resolution failure for recipient MX records
- Firewall or network appliance blocking the connection
- Connection timeout due to high latency or packet loss
How to Fix Error 441
- Wait for automatic retry - most MTAs retry for 24-48 hours
- Verify the recipient domain has valid MX records using MX Lookup
- Check if the recipient domain is reachable from your network
- If persistent, contact the recipient postmaster to report the connectivity issue
Frequently Asked Questions
SMTP error 441 means the recipient's mail server is not responding or cannot be reached. The sending server attempted to connect but received no answer within the expected time, resulting in a connection timeout. This is a temporary error typically caused by the recipient's server being offline, overloaded, or blocked by firewall rules. Your mail server will automatically retry delivery.
First, verify the recipient's email address is correct and the domain exists by checking its MX records. Ensure your own network connection is stable and that your firewall is not blocking outbound SMTP connections on port 25. Wait 15-30 minutes and retry, as the recipient's server may be temporarily offline. If the error persists, contact the recipient's mail administrator to confirm their server is operational and accepting connections.
SMTP 441 is almost always a problem with the recipient's incoming mail server, not your outgoing server. The error indicates the recipient's server is unreachable, offline, or not responding to connection attempts. However, in rare cases, your local firewall, DNS configuration, or ISP may be blocking the connection. Verify your DNS resolution is working correctly and that outbound port 25 traffic is not being blocked.