Windows defender blocking access

If Windows Defender is blocking websites on a personal Windows 11 PC, the most likely causes in the available guidance are web protection or a connected work/school management profile.

Try these checks in order:

1. Check whether a work or school account is connected.
   • Open Settings > Accounts.
   • Review Access work or school.
   • Also review Email & accounts.
   • If any organization account is listed, disconnect or remove it, then restart the PC.
2. Check Microsoft Defender web protection settings.
   • Open Settings > Privacy & Security > Windows Security.
   • Go to App & browser control.
   • Open Reputation-based protection settings.
   • Temporarily turn off items such as:
     • SmartScreen for Microsoft Edge
     • Potentially unwanted app blocking
   • Test the affected site again.
   • Risk: turning off protection lowers security, so turn it back on after testing.
3. Identify what kind of block is happening.
   • In Microsoft Edge, Defender web protection can show a block page.
   • In non-Microsoft browsers, users can see a generic browser error such as a secure connection failure plus a Windows notification.
   • If the message is specifically “This website is blocked by your organization”, that can also be caused by policy-based blocking.
4. If the block is only in Edge and there is a link on the block page, use the false-positive reporting option shown on the Edge block page for SmartScreen-related blocks.
5. If custom entries were added to the Hosts file to block websites, Windows Defender can detect that as SettingsModifier:Win32/PossibleHostsFileHijack. In that specific case, the documented resolution is to exclude the Hosts file from scanning in Windows Defender.
   • Risk: exclusions reduce protection and should be used only if that exact Hosts-file scenario applies.

What the behavior means:

• Defender for Endpoint web protection blocks malicious or unwanted sites at the network protection layer, so the browser can show a generic error while Windows shows a notification.
• In Edge, web threat or web content filtering blocks can show a dedicated block page.

• Respond to web threats
• Web protection in Microsoft Defender for Endpoint
• message that my IT admin has blocked access. - Microsoft Q&A
• Hi, i logged onto my computer this morning and i kept getting notifications about blocked by organization and this is a personal account and PC so can you help me please - Microsoft Q&A
• Hosts file is detected as malware in Windows Defender | Microsoft Support