I traveled to China with my macbook pro and now I am unable to access youtube and facebook. I have seen other posts to other sites that indicate this same problem. Is this a trojan or macid-based restriction?

What happens when you go to you tube?

http://www.youtube.com

Does the page load and you are unable to view videos or does the page not load?

Have you tried with another browser Firefox or Camino?

What happens in Safari if you empty the cache.

Go to your Finder "Go" menu hold the option key to choose "Library".

Then go to Caches folder and find and delete the folder com.apple.Safari

You might also try flushing the DNS cache:

http://support.apple.com/kb/HT5343

It's possible that the system is holding onto routing tables from the Chinese DNS which blocks access to many non-Chinese services.

Regards.

Launch the Network Utility application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Network Utility in the icon grid.

Step 1

Select the Lookup tab and enter

youtube.com

in the address field. Press return. Post the output – the text, please, not a screenshot.

Step 2

Select the Ping tab and do the same.

Select  ▹ System Preferences ▹ Network.

If necessary, click the lock icon in the lower left corner of the preference pane to unlock the settings.

Click Advanced ▹ DNS.

Under DNS Servers you have one or more numerical addresses, such as “192.168.1.1” or “10.0.0.1”. Delete them. Click OK, then Apply. Leave the window open.

Test.