Q: Safari does not load websites properly

I suggest you start by taking the steps recommended in this support article.

DNS Settings - Troubleshoot

Please read this whole message before doing anything.

This procedure is a test, not a solution. Don’t be disappointed when you find that nothing has changed after you complete it.

Step 1

The purpose of this step is to determine whether the problem is localized to your user account.

Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”

While logged in as Guest, you won’t have access to any of your documents or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this behavior; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.

Test while logged in as Guest. Same problem?

After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.

*Note: If you’ve activated “Find My Mac” or FileVault, then you can’t enable the Guest account. The “Guest User” login created by “Find My Mac” is not the same. Create a new account in which to test, and delete it, including its home folder, after testing.

Step 2

The purpose of this step is to determine whether the problem is caused by third-party system modifications that load automatically at startup or login, by a peripheral device, by a font conflict, or by corruption of the file system or of certain system caches.

Please take this step regardless of the results of Step 1.

Disconnect all wired peripherals except those needed for the test, and remove all aftermarket expansion cards, if applicable. Start up in safe mode and log in to the account with the problem.

Note: If FileVault is enabled in OS X 10.9 or earlier, or if a firmware password is set, or if the startup volume is a software RAID, you can’t do this. Ask for further instructions.

Safe mode is much slower to start up and run than normal, with limited graphics performance, and some things won’t work at all, including sound output and Wi-Fi on certain models. The next normal startup may also be somewhat slow.

The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

Test while in safe mode. Same problem?

After testing, restart as usual (not in safe mode) and verify that you still have the problem. Post the results of Steps 1 and 2.

Having the same problem. So far my solution has been to use Firefox.

I'm having the same problem on multiple Macs - and on Safari on iPhones when connected to my home wifi.  Seems like my troubles began on April 1 when my reliable Verizon FIOS service was transitioned to Frontier Communications.

On Macs, sometimes pages won't load in Safari.  They'll hang for about a full minute, then say "Server not found" or something similar.  If I click reload they often come up.  The same websites tend to load the first time in Firefox or Chrome. 

On iPhones, Safari is behaving similarly when connected to wifi with this new Frontier service.  Websites fail to load, then load on retry.  If I turn off wifi, they load just fine over cellular service.

Also, I see connection problems with some other applications on Mac.  For example Postbox sometimes fails to send a message, and then it works when I try again. 

I sure would like to figure out how to fix this.  It's extremely frustrating to have a network that works "sometimes, on the second or third try".  I spent an hour with Frontier support and they declared it a "computer problem, not their network".

Safari - Unsupported third-party add-ons may cause Safari to unexpectedly quit or have performance issues

Safari doesn't load a page or webpage items are missing

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