If some visitors can see your website but others cannot, and the affected visitors are behind a corporate proxy, VPN, or content filter, the issue is usually on their network's side rather than your hosting. Here is what causes this and what you can do about it.
The visitor's proxy or content filter is blocking your site
Corporate networks, school networks, and some ISPs use web filtering proxies that block categories of websites. If your site is miscategorized (for example, flagged as "uncategorized" or "web hosting"), the proxy may block access. The visitor needs to contact their network administrator to whitelist your domain.
01. Why Proxies Block Websites
Web proxies sit between the visitor and the internet. Every request goes through the proxy first, which decides whether to allow or block it. Proxies block sites for several reasons:
- Content filtering - Corporate and school proxies block categories like "adult content," "gaming," "social media," etc. New or uncategorized sites often get blocked by default.
- Reputation scoring - Some proxy systems check the domain's age, SSL status, and hosting IP against reputation databases. Shared hosting IPs that have previously hosted spam or malware sites may have a lower reputation score.
- Geo-blocking - Some networks restrict access to sites hosted in certain countries or regions.
- SSL/TLS version requirements - Strict proxy configurations may reject connections to sites using older TLS versions or certain cipher suites.
02. Proxy Caching Issues
Proxies cache web pages to reduce bandwidth usage. If you recently updated your website but visitors behind a proxy still see the old version, the proxy is serving a cached copy.
You can help by setting proper cache-control headers in your .htaccess file:
<IfModule mod_headers.c>
Header set Cache-Control "no-cache, must-revalidate"
Header set Pragma "no-cache"
</IfModule>This tells proxies and browsers not to cache the page and to always fetch a fresh copy from the server. Use this selectively (not on static assets like images and CSS) to avoid hurting performance for everyone.
For more on cache headers and .htaccess, see our Complete Guide to .htaccess. For browser caching issues without a proxy involved, see Updated My Site But Still See Old Pages.
03. Server Firewall Blocking Proxy IPs
In some cases, the server firewall may be blocking the proxy's IP address. This happens when:
- Multiple users behind the same proxy trigger brute-force protection. All proxy users share the same outgoing IP, so if one user enters the wrong cPanel or email password several times, the firewall blocks the IP, which blocks everyone behind that proxy.
- Rate limiting - Many requests from the same IP (the proxy) can look like a DDoS attack to the firewall.
The visitor can check if their IP is blocked using our Firewall Unblock tool. If the proxy IP is blocked, they can unblock it from there, or you can open a support ticket and ask us to whitelist the IP.
04. What You Can Do
- Make sure your site uses HTTPS - Some proxies block unencrypted HTTP sites by default. Having a valid SSL certificate helps. See SSL Certificates and HTTPS.
- Check your domain reputation - Use tools like Google Safe Browsing (
https://transparencyreport.google.com/safe-browsing/search) to see if your domain is flagged. If it is, clean up any malware and request a review. - Ask the visitor to try without the proxy - If they can access your site from their phone (off the corporate network), the proxy is confirmed as the cause.
- Contact us about IP reputation - If multiple visitors report issues, the shared hosting IP may have a reputation problem. We can investigate and potentially move your site to a clean IP.
Multiple Visitors Affected?
If several people report they cannot reach your site, open a ticket with their locations and any error messages they see. We will check the server side.
Open a Support TicketFrequently Asked Questions
Why can some visitors behind a proxy or VPN not see my site?
When only visitors on a corporate proxy, VPN, or content filter are affected, the issue is usually on their network, not your hosting. Their proxy may cache an old version, block the category, or present a shared IP that a security rule is throttling.
Could my server firewall be blocking a proxy?
It can. If many users share one proxy IP and that IP triggers the firewall, for example from aggregated request volume, legitimate users behind it can be blocked. If you suspect this, contact support with the proxy IP so we can review it.
How do I tell if it is my site or the visitor's network?
Test the site from a different network and on an up-or-down checker. If it loads everywhere except behind one proxy or network, the problem is that network's filtering or caching, not your hosting. A timestamp or Ray ID helps support investigate.
What can I do if a proxy is blocking my visitors?
You cannot control a third-party proxy, but you can make sure your site is not accidentally triggering blocks: use HTTPS, avoid content categories that filters flag, and ask support to check whether a shared proxy IP is firewall-blocked on the server side.
Quick Recap
- Most proxy blocks are on the visitor's network - Not something you can fix directly
- Ensure your site uses HTTPS - Proxies are more likely to block plain HTTP sites
- Check if the proxy IP is firewall-blocked - Use the unblock tool
- Set cache-control headers - Prevents proxies from serving stale content
- Ask affected visitors to test off their network - Confirms the proxy is the cause
Understanding proxy and access issues · Last updated November 2026 · Browse all General articles
