Why does my code open two windows?
<p>I'm trying to open a .pdf file in separate tab/window. It's working, but it opens two windows to show the .pdf.The code I used is as follows. </p>

<pre><code>LinkButton btn = (LinkButton)(sender);
string value = btn.CommandArgument;
imfImageFile = LocalStaticData.UniImageResult;
string path = imfImageFile.WindowsPath;

if (path != "")
{
    Session["OpenPDFImage"] = path;                
    ScriptManager.RegisterStartupScript(Parent.Page, GetType(),
    Guid.NewGuid().ToString(), "openPdf(\"../InvoiceReport.aspx\" );", true);
}
</code></pre>

<p>JavaScript: </p>

<pre><code>function openPdf(href) {
    window.open(href);
}
</code></pre>
