Response.write problem in windows7.

Hi.
I am making Download Page.
And Code is located below
Problem is that it is ok in windows xp but popup a windows for 1 second and close in windows 7.
what's the problem?

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Public Sub executeFile()
Dim fileName  as String = "test.pdf" Dim fileExten As String = "" Dim ContentType As String = "" Dim AddHeader As String = "attachment; filename={0}" Dim filePath As String = "../Education_AttrFile/{0}" 'Dim filePath As String = ConfigurationSettings.AppSettings("FILEPATH").ToString() + "{0}"
fileExten = fileName.Substring(InStrRev(fileName, "."))  AddHeader = String.Format(AddHeader, fileName) filePath = String.Format(filePath, fileName)
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