Undefined index: image3

You are probably looking for this:

 <form action = "#" method = "POST">
        <?php
            $am=$_GET["am"];
            $res=mysql_query("select * from blotterreport where subject like('$am%')");
            echo "<table border="1">";
            while ($row=mysql_fetch_array($res)) {
                echo "<tr>";
                echo "<td>"; echo $row["entrynumber"]; echo"</td>";
                echo "<td>"; echo $row["natureofcase"]; echo"</td>";
                echo "<td>"; echo $row["month"]; echo"</td>";
                echo "<td>"; echo $row["subject"]; echo"</td>";
                echo "<td>"; echo "<img src=view.png onclick= width=100% height=5%/>"; echo"</td>"; /**this is the undefined index**/
                echo "<td>"; echo "<img src=edit.png onclick= width=100% height=5%/>"; echo"</td>"; /**this is the undefined index**/
                echo "</tr>";
            }

        ?>
    </form>

The indexes of the row relate to the column names of your database table. I doubt you have a database column named "<image src=edit.png onclick= width=100% height=5%/>".

You do not need that many ‘echo’ commands.