xml page not displayed

Hi,I amfacing problem in B2B(HTTP-IDOC)scenario.the problem is we posted PO through XI to vendor .XI processed successfylly. but here the probelm is , in SXMB_MONI in the place Response i am getting below message PAGE CANNOT BE DISPLAYED. but my peer geeting correctly . he is in US. i am in india. Actually i dont have access to internet. Is this reason?or my machine problem or any other reason.?

<b>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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Access is denied. Error processing resource 'http://xml.cxml.org/schemas/cXML/1.2.011/cXML.dtd'.

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