Some websites give me the message "Safari can't find the server"!

Mac Safari

1. Power off the router. Unplug it from the wall. Wait a while.

Plug it back to the wall. Power the router on. Wait until all the lights are lit properly. It will take a while.

Restart the computer.

Start up in Safe Mode.

http://support.apple.com/kb/PH14204

2. Delete Caches.db

Close all windows and quit all applications.

Hold "option" key down and click "Go" menu in the Finder menu bar.

Select "Library" from the dropdown.

Library > Caches > com.apple.Safari > Caches.db

Right click the Caches.db file and select "Move To Trash.

Close windows and relaunch Safari.

3. Empty Caches

Safari > Preference > Advanced

Checkmark the box for "Show Develop menu in menu bar".

Develop menu will appear in the Safari menu bar.

Click Develop and select "Empty Caches" from the dropdown.

If you're running Safari on Windows, get rid of it. It's years out of date and should not be used.

If you are searching for something on Google, make sure you are typing in the search bar on the right. The one on the left is for the URL since Safari for Windows is version 5.1.7 and it is outdated.