Preprocessor directives must appear as the first non-whitespace character on a line

<td><% if(# Eval("Path") == null){%><asp:LinkButton CommandArgument='<%# Eval("ID") %>' ID="btnin" OnClick="btnin_Click" runat="server" PostBackUrl="walkin.aspx?<%# Eval("ID") %>" Text="add file"></asp:LinkButton><%}
                      else {%>file: <%# Eval("Path"); }%></td>
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