TL;DR
Your browser or network is blocking websites listed as dangerous. This guide helps you understand why, check the lists, and decide what to trust – carefully.
1. Why Websites Get Blocked
Websites get blocked for security reasons. Common causes include:
- Malware: The site distributes viruses or other harmful software.
- Phishing: It tries to steal your personal information (passwords, bank details).
- Spam: It sends unwanted emails or redirects you to suspicious content.
- Harmful Content: The site contains illegal or inappropriate material.
These blocks come from different sources:
- Your Browser: Chrome, Firefox, Edge have built-in protection.
- Your Operating System: Windows Defender, macOS security features.
- Antivirus Software: Norton, McAfee, Bitdefender etc.
- Firewall: Your network’s security system.
- DNS Provider: Companies like Cloudflare or Google Public DNS offer threat filtering.
2. Checking Block Lists
Several websites maintain lists of known bad URLs. Here are some to check:
- Google Safe Browsing: https://transparencyreport.google.com/safe-browsing/search
- VirusTotal: https://www.virustotal.com/ (Enter the URL to scan it with many antivirus engines)
- URLVoid: https://urlvoid.com/
How to use Google Safe Browsing:
- Go to the Google Safe Browsing site (link above).
- Enter the website address in the search box.
- If it’s listed, you’ll see a warning message.
3. Understanding Browser Warnings
Browsers usually show clear warnings when they block a site:
- Chrome: “This page may be harmful” or “Deceptive site ahead”.
- Firefox: “Warning: Potential Security Risk Ahead”.
- Edge: Similar warnings about dangerous sites.
Important: Don’t ignore these warnings! They are there for a reason.
4. Temporarily Allowing a Website (Use with Caution!)
If you *really* trust the website, and the block seems like a mistake, you can sometimes add an exception. This is risky – only do it if you are sure!
Chrome
- Click “Advanced” on the warning page.
- Choose “Proceed to [website address] (unsafe)”.
Firefox
- Click “I Understand the Risks”.
- Add an exception for the website.
Edge
- Click “Advanced” on the warning page.
- Choose “Proceed to [website address] (unsafe)”.
5. Checking Your Antivirus/Firewall Settings
Your antivirus or firewall might be blocking the site independently of your browser.
- Antivirus: Open your antivirus software and look for a “blocked sites” list or recent scan history. You may need to add an exception there.
- Firewall: Check your firewall logs (usually in the settings) to see if the site is being blocked. Adding it as a trusted site might be necessary.
6. DNS Filtering
If you use a custom DNS provider, they may have stricter filtering rules.
- Cloudflare: Check your Cloudflare dashboard for any blocked domains or filtering settings.
- Google Public DNS: Google’s DNS doesn’t offer much customization; if it’s blocking a site, it’s likely due to widespread reports of malicious activity.
You can temporarily switch back to your ISP’s default DNS servers to see if that resolves the issue (but remember this might reduce your cyber security protection).
7. What If You Still Can’t Access It?
- Contact the Website Owner: Let them know their site is being blocked and ask them to investigate.
- Report a False Positive: If you believe the block list has made an error, report it to the relevant provider (Google Safe Browsing, VirusTotal etc.).
- Consider Another Browser/Device: Try accessing the site from a different browser or computer to rule out local issues.