Error: The server returned an invalid or unrecognized response

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			<table border=0  bgcolor="" width= cellpadding="0" cellspacing="0">	

			<form action="teacher.asp?work=2" method="post">							
			 			 			 			 	
			<tr><td align="right" bgcolor=""><font class="title"><b>รหัสวิชา <img src="skin1\arrow.gif"></td><td>&nbsp; 1204201</td></tr>
			<tr><td align="right" bgcolor=""><font class="title"><b>ชื่อวิชา <img src="skin1\arrow.gif"> </td><td>&nbsp; OOP2013 กลุ่ม 4</td></tr>
			<tr><td align="right"  bgcolor=""><font class="title"><b>หน่วยกิต <img src="skin1\arrow.gif"> </td><td>&nbsp; </td></tr>
			<tr><td align="right" width="20%" bgcolor=""><font class="title"><b>ภาคเรียนที่ <img src="skin1\arrow.gif"> </td><td>&nbsp;1/ 2556</td></tr>
			<tr><td align="right" valign="top"  bgcolor=""><font class="title"><b>คำอธิบายวิชา <img src="skin1\arrow.gif"> </td><td>&nbsp;<div></td></tr>
			<tr><td align="right" valign="top"  bgcolor=""><font class="title"><b>แผนการสอน <img src="skin1\arrow.gif"> </td><td>&nbsp; </td></tr>
			<tr><td align="right" valign="top"  bgcolor=""><font class="title"><b>รายละเอียดอื่นๆ<img src="skin1\arrow.gif"> </td><td>&nbsp;</td></tr>
			<tr><td align="right" valign="top"  bgcolor=""><font class="title"><b>เกณฑ์การตัดเกรด <img src="skin1\arrow.gif"> </td>
			<td><table border="0">
			<tr><td><b>A <td><img src="skin1\to.gif"></td></td><td>80</tr>
			<tr><td><b>B+<td><img src="skin1\to.gif"></td></td><td>75</tr>
			<tr><td><b>B <td><img src="skin1\to.gif"></td></td><td>70</tr>
			<tr><td><b>C+ <td><img src="skin1\to.gif"></td></td><td>65</tr>
			<tr><td><b>C <td><img src="skin1\to.gif"></td></td><td>60</tr>
			<tr><td><b>D+ <td><img src="skin1\to.gif"></td></td><td>57</tr>
			<tr><td><b>D <td><img src="skin1\to.gif"></td></td><td>50</tr>
			<tr><td><b>F <td><img src="skin1\to.gif"></td></td><td>0</tr>							
			</table>																															
			
			</td></tr>
			</form>
			</table>