function CheckURL(byval A_strUrl)
 set XMLHTTP = Server.CreateObject("Microsoft.XMLHTTP")
 XMLHTTP.open "HEAD",A_strUrl,false
 XMLHTTP.send()
 CheckURL=(XMLHTTP.status=200)

 set XMLHTTP = nothing
end function

Dim imgurl
imgurl="img/weste_net.gif"

if CheckURL(imgurl) then
 response.write "圖片存在"
else
 response.write "圖片不存在"
end if

還有用JavaScript來判斷遠程圖片是否存在的代碼：

var oReq = new ActiveXObject("Microsoft.XMLHTTP")
oReq.open("Get","img/weste_net.gif",false);
oReq.send();

if(oReq.status==404)
 alert('不存在');
else
 alert("存在")