Summary
Click tracking links from ESPs are blocked due to a combination of reputation, security, and technical factors. Poor URL, domain, sender, and IP reputation due to spam activity, phishing attempts, or blocklist listings trigger security software. Shared hosting risks, compromised accounts, short domain history, suspicious redirects, missing SSL certificates, uncommon TLDs, brand misalignment, and inaccurate URL categorization contribute to the problem. Experts recommend monitoring reputations, using dedicated resources, maintaining security, ensuring proper SSL setup, and aligning brand identity to avoid blocks.
Key findings
- Reputation is Key: Poor URL, domain, sender, and IP reputation due to spam, phishing, or blocklists are major factors.
- Shared Hosting Risks: Shared hosting can expose your links to risks from other users' malicious activities.
- Security Vulnerabilities: Compromised accounts and a lack of proper security measures can lead to blocks.
- Technical Issues: Missing SSL certificates, suspicious redirects, and uncommon TLDs raise red flags.
- Brand Alignment: Mismatched branding and domain registration inconsistencies contribute to suspicion.
Key considerations
- Monitor Reputation: Actively monitor URL, domain, sender, and IP reputation using available tools.
- Dedicated Resources: Use dedicated IPs and domains for click tracking to avoid shared hosting risks.
- Implement Security: Maintain robust security measures, including SSL certificates and regular malware scans.
- Follow Best Practices: Avoid suspicious redirects, URL shorteners, and uncommon TLDs.
- Align Branding: Ensure consistent branding across sending domains, click tracking links, and website content.
- Request Re-evaluation: If flagged, submit your domain for re-evaluation to security providers and blocklist operators.
What email marketers say
10 marketer opinions
Click tracking links from ESPs can be blocked as dangerous for several reasons, primarily related to reputation. The reputation of the URL itself, the domain it resides on, and the IP address of the server hosting the domain all play a role. Negative factors include association with spam, use of shared hosting where other users engage in malicious activities, a short domain history, use of cloaked redirects or URL shorteners, absence of HTTPS and a valid SSL certificate, uncommon TLDs, misalignment with brand identity, and a poor overall sender reputation. Security software flags these links based on these factors to protect users from potential threats.
Key opinions
- URL Reputation: The reputation of the click tracking URL is critical. A new URL or one associated with spam is likely to be blocked.
- Shared Hosting Risks: If the ESP uses shared hosting for click tracking, the actions of other users on the same server can negatively impact your links.
- Domain Age Matters: The age and history of the click tracking domain are important. Newer domains or those with a history of spam are more likely to be flagged.
- Suspicious Redirects: Using cloaked redirects or URL shorteners can make links appear suspicious and lead to blocking.
- SSL Security: Lack of HTTPS and a valid SSL certificate can trigger warnings and blocks.
- Brand Alignment: Click tracking domains should align with your brand and sending domain to avoid appearing suspicious.
Key considerations
- Monitor Reputation: Actively monitor the reputation of your click tracking domain, URL, and sending IP address.
- Use Dedicated Resources: Consider using dedicated hosting for click tracking to avoid the risks associated with shared hosting environments.
- Establish Domain History: Warm up new click tracking domains gradually to build a positive reputation.
- Avoid URL Shorteners: Use direct links or reputable click tracking services instead of URL shorteners or cloaked redirects.
- Implement HTTPS: Ensure that your click tracking domain uses HTTPS and has a valid SSL certificate.
- Maintain Brand Consistency: Ensure that your click tracking domain aligns with your brand and sending domain to build trust.
Marketer view
Email marketer from EmailAnalysis.com warns that click tracking domains that don't align with your brand or sending domain can appear suspicious and lead to blocks.
14 Oct 2022 - EmailAnalysis.com
Marketer view
Email marketer from StackExchange explains that URL reputation is a crucial factor. If the click tracking domain is new or has been associated with spam, security software might block it.
24 Apr 2025 - StackExchange
What the experts say
3 expert opinions
Click tracking links from ESPs are blocked as dangerous due to multiple factors related to security and reputation. A compromised customer on a shared ESP click tracking domain can lead to all customers being blocked. Poor sender reputation stemming from spam complaints or blocklist listings heavily impacts link deliverability. Using short link domains with a bad reputation also negatively affects campaigns.
Key opinions
- Compromised Domains: A compromised customer on a shared ESP click tracking domain can result in all customers being blocked.
- Sender Reputation: Poor sender reputation from spam complaints or blocklist listings negatively affects link deliverability.
- Short Link Reputation: Using short link domains with bad reputations can harm email campaigns.
Key considerations
- Security Audits: Regularly audit your website security to prevent compromises that could affect your click tracking links.
- Reputation Monitoring: Continuously monitor your sender reputation and promptly address any issues.
- Avoid Short Links: Avoid using short link domains with poor reputations. Consider using reputable services or direct links.
Expert view
Expert from Word to the Wise highlights that using short link domains with poor reputations will negatively affect the deliverability of your email campaigns. This includes click tracking links utilizing those short link domains. She suggests avoiding URL shorteners altogether or using a reputable service.
7 May 2023 - Word to the Wise
Expert view
Expert from Spam Resource emphasizes that a poor sender reputation, often stemming from spam complaints or being listed on blocklists, significantly impacts whether click tracking links are flagged as dangerous. He also advises that monitoring your sending reputation is crucial.
21 Jun 2023 - Spam Resource
What the documentation says
5 technical articles
Click tracking links from ESPs are blocked as dangerous because security providers like Norton, Google Safe Browsing, Spamhaus, Palo Alto Networks, and BrightCloud flag them based on various criteria. These include malware detection, phishing attempts, suspicious behavior, spam activity, and incorrect or malicious categorization. If a click tracking domain triggers these flags or is listed on a blocklist, it is likely to be blocked by security software and browsers.
Key findings
- Malware and Phishing Detection: Norton and Google Safe Browsing flag websites hosting malware or engaging in phishing activities, leading to blocks.
- Spam Activity: Spamhaus maintains blocklists of domains and IPs associated with spam, causing affected click tracking links to be blocked.
- URL Categorization: Palo Alto Networks' URL filtering service categorizes URLs, and incorrect or malicious categorization can lead to blocking.
- URL/IP Reputation: BrightCloud provides URL and IP reputation services; a poor reputation can cause security vendors to block click tracking links.
Key considerations
- Regular Security Checks: Regularly scan your website and click tracking domain for malware and phishing attempts to prevent being flagged.
- Monitor Blocklists: Check if your click tracking domain is listed on Spamhaus or other blocklists and take steps to be removed if necessary.
- Correct Categorization: Ensure that your click tracking domain is correctly categorized by URL filtering services like Palo Alto Networks.
- Maintain a Good Reputation: Take proactive steps to maintain a positive URL and IP reputation, as assessed by services like BrightCloud.
Technical article
Documentation from Spamhaus explains that they maintain blocklists of domains and IPs associated with spam activity. If a click tracking domain is listed on a Spamhaus blocklist, it's likely to be blocked by security software.
1 Mar 2023 - Spamhaus
Technical article
Documentation from Palo Alto Networks explains that their URL filtering service categorizes URLs based on content and reputation. Incorrect or malicious categorization of a click tracking domain can lead to blocking.
26 May 2023 - Palo Alto Networks
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