Check your HOSTS file to make sure its not blocking any related websites.
http://support.microsoft.com/kb/972034
Either read and follow the "Let me fix it myself" or run the "Microsoft Fix It" to automatically reset it.
If that doesn't work, if Internet Explorer is your default web browser (as in the one which opens when you click to see your contacts profile), go to Tools > Internet Options and browse the settings to see if any websites are blocked (e.g. under Security > Restricted Sites, etc.). If not, you can try going to the Advanced tab and click 'Reset' to reset all settings to default.
If you're using Firefox, go to Tools > Options and check if any websites are blocked.
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