Summary
Sanesecurity errors in Outlook occur when a URL in your email is flagged as malicious by Sanesecurity's JURLBL, an automated database of spam and malware URLs. This results in email blocks and 550 errors, indicating permanent delivery failure. Key factors contributing to this include poor URL reputation, incorrect SPF records, issues with shared hosting IPs, use of URL shorteners, sender reputation problems, and missing DKIM/DMARC. Analyzing the specific error message, checking blocklists, understanding the JURLBL hex suffix, and ensuring proper email authentication are crucial for resolving these errors. Be aware that Outlook filters might also cause false positives and contacting Sanesecurity might not be necessary if the flagged URL is genuinely problematic.
Key findings
- JURLBL Listing: A URL in your email is listed in Sanesecurity's JURLBL, causing email blocks.
- Automated Listing: JURLBL listing is automated upon detection of malicious URLs.
- 550 Error: 550 error indicates permanent failure due to spam content or policy reasons.
- URL Reputation: Poor URL reputation contributes to emails being flagged as spam.
- Authentication Issues: Incorrect SPF records and lack of DKIM/DMARC can cause deliverability problems.
- Hex Suffix Meaning: The hex suffix in JURLBL helps identify the reason for the URL being listed.
- Outlook False Positives: Outlook filters can cause false positives.
Key considerations
- Check JURLBL: Verify if any URLs in your email are listed in Sanesecurity's JURLBL.
- Analyze Error Message: Carefully review the error message associated with the bounce.
- Check URL Reputation: Use tools to check the reputation of your URLs.
- Correct SPF Records: Ensure your SPF records are properly configured.
- Implement DKIM/DMARC: Implement DKIM and DMARC for better email authentication.
- Assess Hosting Environment: Consider impact from shared hosting.
- Avoid Shorteners: Avoid the use of URL shorteners.
- Investigate Hex Suffix: Use the hex suffix in the JURLBL listing to identify the issue
What email marketers say
8 marketer opinions
Sanesecurity errors in Outlook indicate that your emails are being blocked due to a URL within your email matching an entry in the Sanesecurity's JURLBL database, which identifies sources of spam. A 550 error in a bounce message confirms the permanent failure of email delivery, often due to spam content. Poor URL reputation, incorrect SPF records, shared hosting IP issues, URL shorteners, sender reputation, and lack of DKIM can contribute to this issue. Addressing these areas is crucial for resolving the problem.
Key opinions
- JURLBL Block: A URL in your email is listed in Sanesecurity's JURLBL, causing it to be flagged as spam.
- 550 Error: A 550 bounce error indicates permanent email delivery failure due to spam content.
- URL Reputation: Poor URL reputation can cause emails to be blocked. Check if your URLs are on any blocklists.
- SPF Records: Incorrect SPF records can lead to deliverability issues.
- Shared Hosting: Shared hosting environments can impact email reputation if other users send spam.
- URL Shorteners: Using URL shorteners can negatively impact deliverability.
- Sender Reputation: Sender reputation and non-spammy email content are critical for deliverability.
- DKIM: Lack of DKIM can cause deliverability issues.
Key considerations
- Check JURLBL: Verify if any URLs in your email are listed in Sanesecurity's JURLBL.
- Analyze Bounce: Examine the specific reason provided in the 550 bounce message.
- URL Reputation Scan: Use tools to check the reputation of URLs used in your emails.
- SPF Configuration: Ensure your SPF records are correctly configured.
- Hosting Environment: Consider the impact of shared hosting on your email reputation and explore dedicated options if necessary.
- Avoid Shorteners: Refrain from using URL shorteners in your emails.
- Content Quality: Ensure email content avoids spammy characteristics.
- Implement DKIM: Implement DKIM for email authentication.
Marketer view
Email marketer from Stack Overflow indicates that incorrect SPF records can cause email deliverability issues. If your SPF record is not set up correctly, receiving servers may flag your emails as spam or block them entirely.
26 Jul 2021 - Stack Overflow
Marketer view
Email marketer from Reddit says that it's important to check if your URLs are listed on any blocklists. Poor URL reputation can be a reason for emails getting blocked and tools exist to check URL reputation.
16 Apr 2025 - Reddit
What the experts say
3 expert opinions
Sanesecurity errors in Outlook are triggered when a URL within your email is flagged as malicious and listed in their JURLBL. Examining the specific error message in the email bounce is essential for diagnosing the issue. The hexadecimal suffix in the JURLBL listing can help pinpoint the exact URL causing the problem. Often, the flagged URL is legitimately problematic, such as mmtrkr.com, so it's often not a false positive and bugging Sanesecurity is not advised.
Key opinions
- JURLBL Listing: Sanesecurity errors indicate a URL in your email is listed in their JURLBL, flagging it as malicious.
- Hex Suffix: The hexadecimal suffix in the JURLBL listing can identify the specific problematic URL.
- Error Message: Analyzing the specific Sanesecurity error message in the bounce is crucial for diagnosis.
- Legitimate Flagging: The flagged URL is often genuinely problematic, not a false positive.
Key considerations
- Check Error Message: Carefully review the Sanesecurity error message in the email bounce.
- Identify URL: Use the hexadecimal suffix (if present) to identify the specific URL causing the issue.
- Assess URL: Evaluate whether the flagged URL is legitimately associated with malicious content.
- Avoid Contacting: Refrain from contacting Sanesecurity unless you have strong evidence of a false positive.
Expert view
Expert from Word to the Wise explains that the hexadecimal suffix in a Sanesecurity JURLBL listing often identifies the specific URL that triggered the listing. This can help you pinpoint the problematic link in your email.
25 Mar 2024 - Word to the Wise
Expert view
Expert from Email Geeks explains that jurlbl lists URLs of bad content, so headers won’t help Sanesecurity identify the problem. He also mentions that mmtrkr.com is likely the problem and, if it's Mazzel, it doesn't feel like a false positive. Recommends not bugging them as it’s a reasonable listing.
23 Sep 2024 - Email Geeks
What the documentation says
5 technical articles
Sanesecurity errors in Outlook arise because a URL in your email has been automatically detected in spam or malware by Sanesecurity's systems and added to the JURLBL. Outlook's filters can sometimes generate false positives, blocking legitimate emails. The hexadecimal suffix in the JURLBL entry identifies the specific problem with the URL. A 550 SMTP error indicates a permanent failure due to policy reasons, spam, or viruses. Implementing a DMARC policy helps manage how email receivers handle messages failing authentication checks, preventing spoofing and phishing.
Key findings
- Automated JURLBL Listing: URLs are added to Sanesecurity's JURLBL automatically upon detection in spam or malware.
- Outlook Filters: Outlook's filters can cause false positives, blocking legitimate emails.
- Hex Suffix Purpose: The hexadecimal suffix in JURLBL entries identifies the specific issue with the URL.
- 550 Error Meaning: A 550 SMTP error indicates permanent failure due to policy, spam, or viruses.
- DMARC Policy Benefit: DMARC policies help manage email authentication failures and prevent spoofing.
Key considerations
- Review Sanesecurity Listing: Check the JURLBL to see if any URLs in your email are listed.
- Address False Positives: Understand that Outlook filters can sometimes block legitimate emails. Investigate why.
- Analyze Hex Suffix: Use the hex suffix to understand why a particular URL was flagged by Sanesecurity.
- Investigate 550 Error: Further analyze the 550 error to understand the specific policy reason for the failure.
- Implement DMARC: Implement and correctly configure a DMARC policy to improve email authentication.
Technical article
Documentation from dmarcian explains that a DMARC policy helps domain owners specify how email receivers should handle messages that fail SPF or DKIM checks. Implementing DMARC correctly helps prevent email spoofing and phishing attacks.
1 Sep 2024 - dmarcian
Technical article
Documentation from Sanesecurity explains that to be listed on JURLBL, their systems will have detected your URL in SPAM or Malware emails. It is an automated listing, and human review is not generally performed unless requested.
6 Sep 2021 - Sanesecurity
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