Hyperlink in gridview column problem

Question

 hi guys iam binding columns from database and showing in gridview but one column is url so i need to give hyperlink that field but if i click on that link iam not able to pass url navigating another page

 

<Columns>

<asp:BoundField DataField="Title" HeaderText=" Title " />

<asp:BoundField DataField="Speaker" HeaderText="Speaker" />

<asp:BoundField DataField="Publisher" HeaderText="Publisher" />

<asp:BoundField DataField="Description" HeaderText="Description" />

<asp:HyperLinkField DataNavigateUrlFields="URL"

DataNavigateUrlFormatString='URL'

DataTextField="URL" HeaderText="urlpa" target="_blank"/>

</Columns>

 

 

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