Safari can't find the server.

If Safari can’t open a website
Several reasons may explain why a website fails to open in Safari. If a website doesn’t open, try the following suggestions.

• Check the web page address: Make sure the web page address you have is correct and that you entered it accurately. Try typing “/index.html” at the end of the address.
• Make sure the computer is set to the correct time and time zone (without this, secure sites may not load).
• Clear the cache and reset Safari. To clear the cache, press Control + Option + E, then click on Empty. Then press Control + R to reload the page.
• Try switching your DNS to Google DNS or Open DNS.
• If clearing the cache doesn’t work, choose the Action menu > Reset Safari, then click Reset and try opening the page again. (The Action menu is located next to the upper right corner of the Safari window and looks like a gear). Note: resetting Safari deletes browsing history and other information. For more information, see:
• If your computer or network is protected by a proxy server or firewall, make sure the network and Internet settings are correct in the Control Panel. Incorrect settings can prevent Safari from connecting to certain websites.
• Contact the website owner
• The webpage may be preventing users from accessing it with Safari. Check with the website owner to confirm this.
• Check if the first part of the address, which identifies the Internet protocol (for example, http or https), is non-standard. If so, Safari cannot open it.
• Ask the website owner if there is a server configuration issue.
• Use the latest version of Safari

If the webpage still does not open, report the problem by opening the Action menu located near the upper right corner of the Safari window (similar to a gear), and choose “Report a bug to Apple”.

:) let me know if it works :)