Summary
Emails sent to Bigpond.net.au addresses, an email service provided by Telstra, are increasingly experiencing bounces and being marked as spam. This can occur even when email sending strategies remain unchanged and other providers show good delivery rates. The issues often stem from content filters, sender reputation, and Bigpond's server capacity, particularly its strict volume thresholds.
Key findings
- Content rejection: Bigpond emails are frequently rejected due to "suspected spam content," including one-on-one customer support replies.
- Reputation decay: Sender reputation can decline over time, affecting delivery even if your strategy hasn't changed.
- Strict volume limits: Bigpond's mail servers enforce very strict volume thresholds, leading to bounces for high or even moderate sending rates.
- Legacy infrastructure: Bigpond is an older provider, which may contribute to server capacity issues and less flexible filtering.
Key considerations
- Analyze bounce messages: Investigate specific error messages like 558 5.7.1 Message content rejected due to suspected spam.
- Monitor reputation: Regularly monitor your sender reputation, as it can degrade without apparent changes in sending habits. This will help you improve your deliverability and avoid spam folders.
- Adjust volume: Adjust email sending volume to Bigpond domains to stay within their strict limits (e.g., below 7500 emails per hour) as high volume can trigger bounces.
- Direct engagement: Consider reaching out to Bigpond support directly if you can provide proof of non-spamming, though this can be challenging.
What email marketers say
Email marketers often report frustrating Bigpond email delivery issues, noting that these problems can arise despite consistent email strategies and good performance with other ISPs. Many attribute this to evolving sender reputation, strict volume limitations imposed by Bigpond, and the general perception of Bigpond as an older, potentially less robust email provider.
Key opinions
- Reputation impact: Marketers acknowledge that reputation can worsen over time, regardless of a stable sending strategy.
- Content flagging: Suspicion of spam content, possibly due to flagged URLs, is a common reason for rejections, even for one-on-one customer support emails.
- Server capacity: Marketers state that Bigpond's servers sometimes struggle with volume, leading to bounces even for smaller sends due to their very strict thresholds.
- IP address issues: Problems with the sending IP addresses are frequently cited as a potential cause for Bigpond rejections.
Key considerations
- Check IPs: Regularly check your sending IPs for any blocklist listings.
- Analyze transient bounces: Review your transient bounce messages to gain insights into specific issues causing rejections from Bigpond.
- Proactive reputation management: Implement strategies for continuous sender reputation improvement to prevent gradual decay, which is vital for overall email deliverability.
- Contact ISP: Some marketers suggest directly contacting Bigpond to resolve issues, as seen in community discussions where users report success after proving non-spamming activity.
Marketer view
A marketer from Email Geeks observes a significant increase in Bigpond bounces, even for one-on-one customer support replies, despite no changes to their email strategy, indicating a unique challenge with this provider.
Marketer view
A user on Spiceworks Community suggests that issues like poor grammar, overuse of capitalization, or problems with SPF, DKIM, DMARC, or TLS are often behind emails being rejected as spam.
What the experts say
Experts in email deliverability emphasize that Bigpond's strict filtering and server limitations are key drivers behind bounces and spam classifications. They highlight the importance of continuous reputation monitoring, meticulous analysis of transient bounce data, and adhering to specific volume thresholds set by the ISP (Internet Service Provider). Even without strategy changes, reputation can degrade, leading to deliverability challenges.
Key opinions
- Reputation is dynamic: Experts emphasize that sender reputation can decline over time, even if the sending strategy remains constant, leading to unexpected delivery issues.
- Content and URLs: They suggest that "suspected spam content" may specifically refer to URLs within the email being flagged as frequently associated with spam.
- Strict volume thresholds: Bigpond is known for having strict volume thresholds, and reviewing transient bounces can provide clues about these limits.
- Sending rate limits: A specific guideline for Bigpond domains is to send at a rate under 7500 emails per hour for all mail, not just from a single sender or IP.
Key considerations
- Continuous monitoring: Continuously monitor your sender reputation to proactively address any negative trends.
- Detailed bounce analysis: Analyze the detailed bounce messages (transient bounces) to understand the specific reasons for rejections, as described in guides on email delivery errors.
- Volume adherence: Adhere strictly to known or inferred volume limits for sending to Bigpond domains to avoid throttling or rejection.
- Understand blocklists: Familiarize yourself with how email blocklists and blacklists work, as they can heavily influence rejections.
Expert view
An expert from Email Geeks (wise_laura) points out that "suspected spam content" could mean that the URLs within your emails are flagged as frequently appearing in spam, advising careful review of included links.
Expert view
An expert from SpamResource emphasizes that proper email authentication, including SPF, DKIM, and DMARC, is crucial for maintaining sender trust and avoiding rejections, especially by strict ISPs like Bigpond.
What the documentation says
While specific Bigpond (Telstra) email delivery documentation is not always publicly comprehensive, general email delivery standards and common ISP practices provide strong guidance. Documentation typically highlights the importance of adhering to standard email protocols (e.g., SPF, DKIM, DMARC), maintaining healthy sender reputation metrics, and respecting volume limits to ensure messages reach the inbox. Error codes, such as 558 5.7.1, are universally recognized indicators of content or reputation-based rejections.
Key findings
- Error codes: Standard email error codes like 558 5.7.1 indicate specific rejection reasons, often related to content or spam filtering.
- Blocklist checks: Mail servers commonly check incoming emails against RBLs (Real-time Blackhole Lists) or other blocklists to filter out suspected spam.
- Temporary issues: Soft bounces can occur due to temporary recipient server issues, such as DNS server downtime or full mailboxes.
- Phasing out: Telstra, Bigpond's parent company, has been phasing out Bigpond email accounts, which could suggest legacy infrastructure challenges contributing to delivery issues.
Key considerations
- Email authentication: Ensure your email authentication (SPF, DKIM, DMARC) is correctly configured to prove sender legitimacy.
- Blocklist monitoring: Regularly monitor your domain and IP against common blacklists and blocklists.
- Content best practices: Be aware that even legitimate emails can be filtered if they contain elements (e.g., certain URLs or phrasing) frequently found in spam, as highlighted in guides on solving email delivery issues.
- ISP-specific policies: Understand that older email services like Bigpond might have unique or less transparent delivery policies compared to modern providers. Additionally, keep in mind that Bigpond email accounts are being phased out.
Technical article
Documentation from SMTP2GO explains that a soft bounce may be caused by a temporary issue with the recipient server, such as a DNS server being down or the recipient's mailbox being full.
Technical article
Noytech's documentation indicates that most receiving mail servers are configured to check incoming mail against RBLs (Real-time Blackhole Lists) to ensure emails originate from trusted sources and are not from spammers.
Related resources
9 resources
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