What causes the 'error message' when accessing links in emails and how can it be resolved?

Summary

Error messages when accessing links in emails can stem from a wide array of issues, including problems with URL validity, security measures enacted by email providers or local software, reputation concerns related to the linked domain or IP address, and configuration errors in email marketing setups. Specific causes range from broken or invalid URLs, Cloudflare blocking suspicious IPs, email client security scans, and blacklisted domains to encoding issues, incorrect tracking parameters, and website changes. Resolving these issues requires a multi-faceted approach, including thorough link testing, ensuring proper URL encoding, verifying domain and IP reputation, configuring email settings correctly, and addressing any potential security blocks or local software conflicts.

Key findings

  • Security Blocking: Email providers (Gmail, Outlook), security services (Cloudflare), and local software (antivirus, ad blockers) actively block links deemed risky.
  • Reputation Matters: Domain and IP reputation significantly impact link accessibility; blacklisted entities trigger error messages.
  • URL Integrity: Invalid, broken, or improperly encoded URLs are a frequent cause of errors.
  • Configuration Issues: Incorrectly set up tracking, personalization, or redirect chains break links.
  • Website Changes: Website redesigns, content removal, and typos lead to broken links if not addressed.

Key considerations

  • Thorough Testing: Rigorously test all links before sending emails across different devices and email clients.
  • Validate URLs: Regularly use link validation tools to identify and fix broken URLs.
  • Check Security Settings: Advise recipients to check their antivirus and ad-blocking settings if links are consistently blocked.
  • Monitor Reputation: Actively monitor domain and IP reputation and take steps to address any issues.
  • Proper Configuration: Ensure all tracking parameters, personalization tags, and redirect chains are correctly configured.
  • Use Reputable Shorteners: Stick to well-known link shorteners and monitor their reputation to avoid being blacklisted.
  • Stay Updated: Keep URLs updated after website changes or content removals, using redirects as necessary.

What email marketers say
10Marketer opinions

Error messages when accessing links in emails can stem from various issues related to URL validity, security measures, and email client configurations. These issues include broken or invalid URLs, link shortener reputation, encoding problems, incorrect tracking parameters, personalization errors, redirect chains, domain reputation, corporate security policies, and interference from image proxies. Resolving these errors requires thorough testing, validation, proper configuration, and addressing potential security blocks.

Key opinions

  • URL Validity: Broken or invalid URLs are a common cause of error messages. Thorough testing and validation are essential.
  • Security Measures: Corporate firewalls, antivirus software, and email client security features can block links deemed unsafe.
  • Configuration Errors: Incorrectly implemented tracking parameters, personalization tags, and redirect chains can lead to broken links.
  • Domain Reputation: If a domain has a poor web reputation the links in emails might not work
  • Encoding issues: URL Encoding Issues. If special characters, or characters not matching what the server expects are in the URL it might break

Key considerations

  • Test Thoroughly: Always test links before sending emails to ensure they are functional across different email clients and devices.
  • Validate URLs: Use link validation tools to check for broken or invalid URLs and fix them promptly.
  • Avoid Shorteners: Be cautious when using URL shorteners, as some are flagged as suspicious and can negatively impact deliverability.
  • Check Security Policies: If links are consistently blocked, check with the IT department to ensure the URL isn't being blocked at the network level.
  • Review Configurations: Double-check tracking parameters, personalization tags, and redirect chains to ensure they are correctly implemented.
  • Monitor Reputation: Maintain a good domain and IP reputation to prevent links from being flagged as unsafe.
Marketer view

Email marketer from Mailjet Blog explains that an incorrect setup of tracking links, particularly when using custom domains for tracking, can cause error messages. They recommend verifying the DNS settings for the custom domain and ensuring that the tracking links are correctly configured in the email sending platform.

June 2023 - Mailjet Blog
Marketer view

Marketer from Email Geeks suggests that something is flagging Marketo's domain with a bad web reputation. He advises using an alternative device to pinpoint where the negative verdict is coming from and addressing it with the appropriate party.

October 2022 - Email Geeks
Marketer view

Email marketer from Email on Acid Blog shares that including tracking parameters incorrectly or exceeding URL length limits can cause email links to break. They recommend keeping URLs concise and using appropriate URL builders to manage tracking parameters effectively.

April 2023 - Email on Acid Blog
Marketer view

Email marketer from SendPulse Blog shares that error messages upon clicking email links can stem from invalid or broken URLs. They recommend thoroughly testing links before sending emails and using link validation tools to ensure all URLs are functional. Additionally, avoiding URL shorteners can improve deliverability, as some are flagged as suspicious.

June 2021 - SendPulse Blog
Marketer view

Email marketer from SuperOffice Blog suggests that excessive redirect chains can cause browsers to time out or refuse to load a page, resulting in an error message. They recommend minimizing redirects and ensuring that each redirect is necessary and correctly configured.

February 2024 - SuperOffice Blog
Marketer view

Email marketer from Litmus Blog answers that certain email clients use image proxies that can sometimes interfere with link tracking or redirect functionality, leading to error messages. They suggest testing emails across various email clients to identify and address these issues.

April 2023 - Litmus Blog
Marketer view

Email marketer from Reddit user u/EmailPro suggests that email links might be blocked by corporate firewalls or antivirus software due to security policies. They advise checking with the IT department to ensure the URL isn't being blocked at the network level.

December 2022 - Reddit
Marketer view

Email marketer from StackOverflow user TechGuru responds that encoding issues within the URL can lead to errors. They suggest ensuring URLs are properly encoded, especially if they contain special characters, and that the encoding matches what the server expects.

November 2023 - StackOverflow
Marketer view

Email marketer from Campaign Monitor Blog says that incorrect personalization tags in URLs can result in broken links. They advise double-checking the personalization code to ensure it's correctly implemented and doesn't introduce invalid characters into the URL.

June 2024 - Campaign Monitor Blog
Marketer view

Email marketer from Neil Patel Blog explains that broken links often result from website changes, typos, or incorrect redirects. He advises regularly checking links using tools like Google Analytics, fixing typos, and ensuring redirects are properly set up to maintain a positive user experience.

March 2022 - Neil Patel Blog

What the experts say
4Expert opinions

Error messages when accessing email links can arise from multiple sources, including Cloudflare blocking suspicious IP addresses, ad blocking or antivirus software on the user's device, and the use of blacklisted link shorteners. Website redesigns, content removal, and typos also contribute to broken links and error messages. Addressing these issues involves investigating network security, checking local device settings, carefully selecting link shorteners, and regularly auditing link integrity.

Key opinions

  • Cloudflare Blocking: Cloudflare might block access if it suspects malicious activity from the user's IP address or network.
  • Local Software Interference: Ad blocking or antivirus software on the user's computer can prevent access to links.
  • Link Shortener Reputation: Using blacklisted link shorteners can lead to error messages.
  • Website Changes: Website redesigns, content removal, or typos can cause broken links.

Key considerations

  • Investigate Security Issues: If Cloudflare is blocking access, investigate the user's network and consider whitelisting the IP address if necessary.
  • Check Local Settings: Advise users to check their ad blocking and antivirus software settings if they encounter link access issues.
  • Choose Reputable Shorteners: Use reputable link shorteners and monitor their reputation to avoid being blacklisted.
  • Audit Links Regularly: Regularly audit links, implement redirects, and ensure URLs are correctly formatted to prevent errors caused by website changes.
Expert view

Expert from Email Geeks shares that the issue could also stem from ad blocking software or anti-virus software installed on the user's computer, suggesting various internal PC factors might be responsible.

May 2023 - Email Geeks
Expert view

Expert from Word to the Wise explains that broken links can occur due to website redesigns, content removal, or typos. She advises regularly auditing links, implementing redirects, and ensuring URLs are correctly formatted to prevent errors.

March 2025 - Word to the Wise
Expert view

Expert from Email Geeks explains that the error message is likely due to Cloudflare blocking access from an IP address suspected of malicious activity. It's a security issue to investigate with the person receiving the error, potentially related to the wifi network they are using or a personal VPN. Al Iverson emphasizes that this issue isn't directly related to email deliverability but rather a web access problem.

August 2021 - Email Geeks
Expert view

Expert from Word to the Wise explains that using reputable link shorteners is crucial as some can be blacklisted and trigger error messages. He advises sticking to well-known services and monitoring their reputation.

September 2022 - Word to the Wise

What the documentation says
5Technical articles

Error messages when accessing links in emails are often triggered by security scans performed by email providers like Gmail and Outlook, Cloudflare's IP reputation system, or blocklists maintained by organizations like Spamhaus. These systems check for malicious content, suspicious IP activity, or blacklisted domains. Ensuring websites are secure (HTTPS), adhering to URL syntax rules, and maintaining a good domain reputation are crucial for preventing these errors.

Key findings

  • Gmail Security Scan: Gmail scans links for malicious content and flags potential security risks or untrusted websites.
  • Cloudflare IP Reputation: Cloudflare blocks access from IP addresses flagged for suspicious activity, often impacting users on compromised networks or VPNs.
  • Outlook Safe Links: Outlook Safe Links rewrites URLs and checks for malicious content, displaying errors if threats are detected.
  • Spamhaus Blocklists: Email clients flag links to domains listed on Spamhaus blocklists, triggering error messages.
  • URL Syntax Violations: URLs that violate syntax rules defined in RFC 3986 (e.g., unescaped characters) can cause errors.

Key considerations

  • Ensure HTTPS Security: Make sure the linked website is secure (HTTPS) to avoid being flagged by email security scans.
  • Maintain IP Reputation: Avoid using networks or VPNs with poor reputations that may be blocked by Cloudflare.
  • Verify Domain Reputation: Check if your domain is on any blocklists and request delisting if appropriate.
  • Adhere to URL Syntax: Ensure URLs comply with RFC 3986 standards and are correctly formatted.
  • Contact Sender for Legitimate Links: If a link is blocked and appears legitimate, contact the sender to report the issue.
Technical article

Documentation from Microsoft explains that Outlook Safe Links rewrites URLs in emails to point to Microsoft servers. When a user clicks the link, Microsoft checks the destination website for malicious content. An error message can appear if the scan detects a threat or if the site is unavailable. They recommend contacting the sender if the link appears legitimate.

May 2022 - Microsoft Support
Technical article

Documentation from Google Support explains that Gmail scans links in emails for malicious content. An error message might appear if the scan identifies a potential security risk, or if the link is to an untrusted or blacklisted website. They recommend ensuring the linked website is secure (HTTPS) and not on any blocklists.

August 2021 - Google Support
Technical article

Documentation from Cloudflare explains that 'Access Denied' errors often appear when a user's IP address is flagged for suspicious activity. Users may encounter such errors clicking email links if their current network or VPN has a poor reputation. Resolution involves switching networks or contacting the website administrator to whitelist the IP.

July 2024 - Cloudflare Support
Technical article

Documentation from RFC 3986 details the official syntax rules for URLs. Violations of these rules (e.g., unescaped characters, incorrect formatting) can lead to errors when a user tries to access the URL from an email. Adherence to the RFC's guidelines is essential for ensuring links function correctly.

April 2023 - RFC Editor
Technical article

Documentation from Spamhaus explains that email links to domains listed on their blocklists can trigger error messages or warnings in email clients. To resolve this, one needs to verify the domain's reputation and request delisting if appropriate.

August 2021 - Spamhaus