Can't Open the Media Library

Hi,

In one site of my site in mutisite, the Media Library isn't opening. It's just shows the loading icon but images never get loaded. http://bit.ly/1PyyLqy

It happens in when trying to add an image in Coursepress media library too. http://bit.ly/1MKeyxg

Can someone please help me to resolve this? Support access is granted! Use it to visit those links.

Thanks.

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