macOS – How to Fix Internet Browsing Issues on Mac OS X

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I can't reach websites using browsers in OS X 10.6.7 on a MacBook Pro, possibly after resuming from sleep. I've had this problem before and it has been solved by a reboot, but I since I got it again I wanted to get to the root of it.

It all starts with Chrome and Safari not being able to browse the Internet. Here's a list of what works and what doesn't:

Doesn't work

Browse Internet in Safari, Chrome and Firefox ("You are not connected to the Internet.")
Adium

Works

ping google.com
wget google.com
curl http://www.google.com
traceroute google.com
nslookup google.com
Browse Internet in any browser with the Charles proxy started
Browse 74.125.39.103 (Google IP) in any browser
Skype

I haven't configured any proxy at all (except for when running with Charles). Other computers on the network can reach Internet just fine. I'm connected to either Ethernet, the AirPort, or both but no combination makes a difference.

I've also tried to use a different DNS provider, Google Public DNS, but that didn't work either (nslookup, ping etc used the new name server without problems).

Visiting the IP number of google.com in the browser works as stated above, and considering ping et al works, it seems to be a DNS issue? What could be causing this?

Best Answer

Problem temporarily solved by running:

sudo killall mDNSResponder

As per this question: MacBook can't use internet, but nslookup and ping both work.

Still doesn't explain why this breaks down on sleep/resume though.

Related Solutions

Macos – How to identify web site inaccessible issue on OSX

Check the error you're receiving:

If you can load the webpage using another browser, but not Google Chrome, check the exact error you're getting by clicking the More information on this error link on the page.

If you're getting "Error 124 (net__ERR_WINSOCK_UNEXPECTED_WRITTEN_BYTES)," see the Error 124 troubleshooting article.

For the following errors, try the solutions below:

Error 101 (net::ERR_CONNECTION_RESET)
Error 2 (net::ERR_FAILED): Unknown error
Error 104 (net::ERR_CONNECTION_FAILED)
Error 105 (net::ERR_NAME_NOT_RESOLVED)
Error 102 (net::ERR_CONNECTION_REFUSED): Unknown error
Error 324 (net::ERR_EMPTY_RESPONSE)

Clear your cookies:

Cookies are files created by websites you've visited to store browsing information, such as your preferences for the website or profile information. A corrupted cookie file may be causing this error to show up. Follow these steps to clear your cookies:

Click the Chrome menu Chrome menu on the browser toolbar.

Select Settings
Click Show advanced settings.
In the "Privacy" section, click Content settings
In the "Cookies" section, click the All cookies and site data.
Click Remove all. Click X to close the dialog.

Make sure Google Chrome is allowed in your antivirus and firewall settings:

Each program works differently, so check your software's help resources for further instructions.

Are you using a proxy? Please try disabling it in system preferences --> Networking --> Active internet connection (usually marked as green circle).

Then click on "Advanced..." button. - Select Proxies tab.

Uncheck "Web Proxy" and "Secure web proxy"

Macos – Mac cannot browse, ping works fine

While an old question, it still appears at the top on Google, so it makes sense to add a new answer.

I found a helpful hint at this Apple discussion. In short, a rogue process could be holding a crazy number of TCP connections. In my case it was Kaspersky that was failing to connect to the update server but seemingly never releasing connections.

To check for this, run:

sudo lsof -n -i TCP

If there's a huge number of open connections (in the hundreds) this might be your issue. Try killing the process that is holding them and see if it helps. After killing Kaspersky (and, probably needlessly, restating WiFi) it all went back to normal for me.

How this affects some sites but not others is beyond me.

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