Website Blocked by Antivirus or Company Firewall
Customers say Norton, McAfee, or their office network is blocking your website — sometimes it is a false alarm, and sometimes the security software has spotted something real.
Common signs of this issue
- A customer sends a screenshot of a Norton, McAfee, Bitdefender, Avast, or similar warning page instead of your site.
- People at larger companies, schools, or government offices say your site is blocked at work but loads fine at home.
- The block message mentions a category such as "malicious", "phishing", "suspicious", "newly registered", or "uncategorized".
- Downloads from your site, such as PDFs or price lists, are stopped or quarantined by antivirus software.
- Emails containing links to your site bounce or get held by a customer's mail filter.
- The site loads fine for you and most visitors, so the problem only shows up through complaints.
Safe checks you can do yourself
None of these require sharing passwords with anyone.
- Ask the person who is blocked for the exact message or a screenshot. It usually names the product doing the blocking and the reason or category. Without that, you are guessing at which of dozens of security vendors to contact.
- Check your domain on VirusTotal (the URL scan). It asks dozens of security vendors at once and shows which, if any, flag your site. One or two flags from minor vendors is common and often a false positive; many flags at once is a strong sign of a real problem.
- Check Google's Safe Browsing site status in Google's Transparency Report. Chrome, Firefox, and Safari all rely on it, so if Google flags your site, far more people are affected than the one customer who complained.
- Look at the vendor's own lookup page. Most major vendors — Norton Safe Web, McAfee, Cisco Talos, Palo Alto Networks, Fortinet FortiGuard, Broadcom (Symantec) Site Review, Microsoft Defender SmartScreen — let you look up how they rate or categorize a site and request a review.
- Before asking anyone to unblock you, make sure the site is actually clean. Ask your host for a malware scan, look for strange pages in a Google site: search, and check for admin users or files you do not recognize.
- Think about recent changes: a new domain, a site move to a new server or IP address, a new download, a link to another site, or a burst of marketing emails. Security vendors react to all of these, and the timing often explains the block.
- If the block is only at one company, ask their IT team what category your site was given. Corporate filters often block uncategorized or newly registered sites by policy even when nothing is wrong with them.
What this usually means
Security software blocks a site for one of two broad reasons. The first is a real problem: the site has been hacked and is serving malware, redirects, or phishing pages, sometimes only to certain visitors, so the owner never sees it. The second is a reputation or category judgment that has nothing to do with infection: the domain is new and has no track record, the site shares a server IP address with bad neighbors, the domain had a bad history under a previous owner, the site was once hacked and the rating was never updated, or an automated system simply put it in the wrong category.
It matters which one you have, because the fixes are opposite. For a real infection, asking vendors to unblock you is pointless — and can backfire — until the site is cleaned. For a false positive, the site is fine and the job is paperwork: submitting a review or recategorization request to each vendor that flags you, with a short, factual description of your business. Most vendors review these within a few days, though timing varies, and each vendor has its own separate process.
Corporate and school firewalls add a third layer. Their filters, such as Cisco Umbrella, Zscaler, Fortinet, or Palo Alto, block by category as much as by threat. A perfectly clean site that is labeled "uncategorized", "newly registered domain", or a category the company restricts will be blocked at that office until the vendor's category is corrected or the company's IT team adds an exception.
What not to do
- Don't tell customers to turn off their antivirus or ignore the warning. It sounds unprofessional, and if the site really is infected you are putting them at risk.
- Don't file unblock requests before confirming the site is clean. Vendors will re-flag an infected site, and repeated bad requests can slow future reviews.
- Don't assume one vendor's block means you are hacked, or that one clean scan means you are fine. Check several sources before deciding.
- Don't argue with a company's IT department about their policy. Ask politely what category they see and request an exception or recategorization instead.
- Don't move the site to a new domain to escape the block. You lose your search standing, and a brand-new domain is more likely to be blocked, not less.
When to get help
If VirusTotal, Google, or your host shows real signs of malware, get help with a proper cleanup before anything else — reputation requests only work once the cause is gone. It is also reasonable to bring someone in when several vendors flag the site, when the block keeps coming back after being cleared, or when you suspect a shared server IP or the domain's past is the issue. Those cases involve checking server logs, IP reputation, and each vendor's separate review process, and a helper who has done it before can work through the list in an organized way while you get on with running the business.
Not sure what to do next?
Answer a few short questions and we'll point you to the safest next step — DIY, a freelancer, or a direct review. No passwords required.
Is this a business website? If this issue may be costing you leads, sales, or trust, you may want a direct review instead of trial and error.
Frequently asked questions
Why is Norton or McAfee blocking my website?
Either their systems detected something harmful, such as malware or a phishing page, or they rated the site as risky based on reputation signals like a new domain, a shared server with bad sites, or an old infection. Their site lookup page usually shows which, and both offer a way for site owners to request a review.
How do I get my website unblocked?
First confirm the site is clean with a malware scan and a check of Google's Safe Browsing status. Then find which vendor is blocking it, look the site up on that vendor's rating or site review page, and submit a review or recategorization request. Each vendor must be contacted separately.
How can I tell if it is a false positive or a real infection?
Check the site on VirusTotal and Google's Safe Browsing status, and ask your host for a malware scan. If only one small vendor flags you and every scan is clean, a false positive is likely. If several vendors or Google flag it, treat it as a real problem until proven otherwise.
Why is my site blocked at my customer's office but not at home?
Company networks use web filters that block whole categories of sites, including uncategorized or newly registered domains, regardless of whether they are dangerous. Asking the company's IT team what category they see, and requesting a correction from the filter vendor, usually solves it.
How long does it take to get unblocked?
It depends on the vendor. Many review requests are handled within a few days, some faster, some slower. If the site is still infected, the request will be declined, so cleanup always comes first.
Will this affect my Google rankings?
An antivirus or company firewall block on its own does not directly change Google rankings. A Google Safe Browsing warning is different and can sharply cut traffic, which is why it is worth checking Google's status as soon as any vendor flags you.