Can’t Browse Web, Can Ping and E-mail
This one is here so I can find it easily next time. I spent most of a day troubleshooting this before I found the solution.
User cannot browse the Web. May be able to browse secured (https) sites, but normal (http) sites blocked. Can ping sites. Can use an e-mail client. Can use Telnet, except for port 80.
- Check firewall settings, anti-virus, anti-spyware, anti-malware. Run full scan with your security software.
- Check proxy settings.
- Connect another computer to see whether there is something filtering out HTTP upstream.
Here’s what you can try next:
- Reboot the computer into safe mode. If you don’t, you won’t be able to do this.
- Log in with a local machine administrator’s account. Open the registry editor.
- Navigate to
3. NOTE: if this key isn’t there, this isn’t your problem and this fix will not help you.
- Restart the computer.
In this case, you’re probably dealing with the leftover pieces of a ZoneAlarm firewall installation.
As the HP discussion site above says:
1. Even if you think you never installed ZoneAlarm (like me), still look out for vdatant.sys, it may be there!
2. You cannot change the registry setting when vdatant.sys is loaded/running, even if you have Admin privileges. You need to boot your machine in safe mode (with or without networking), and then you can edit the registry setting to disable the driver.