Unable to view/edit .xml file

I am in the process of preparing a new Joomla responsive template for a website. Using FileZilla under root directory and a new folder, I could open/edit a newly created .php file (index.php) but unable to open/edit .xml file (templatedetails.xml). I am getting the following message:

The XML page cannot be displayed
Cannot view XML input using style sheet. Please correct the error and then click the Refresh button, or try again later.


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XML document must have a top level element. Error processing resource 'file:///C:/Documents and Settings/Administrator/Loca...

Any help in this regard will be highly appreciated. Thanks in advance.