为什么出现内部服务器错误
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#ss {
position: absolute;
height: 76px;
width: 120px;
left: 1106px;
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<div id="ss"><a href="zhuye.html">回到主页</a></div>
<table width="60%" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td><img src="img/留言板背景.jpg" width="808" height="259" /></td>
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<tr>
<td><table width="800" border="0" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="175" height="270" valign="top"><img src="img/写留言.png" alt="" width="175" height="308" /></td>
<td width="625" valign="top"><form action="" method="post" enctype="multipart/form-data" name="form1" id="form1">
<table width="600" border="0" align="center" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td width="120" height="30" align="right" valign="middle">姓名:</td>
<td height="30"><label for="textfield18"></label>
<input type="text" name="textfield" id="textfield18" /></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">性别:</td>
<td height="30"><p>
<label>
<input type="radio" name="RadioGroup1" value="单选" id="RadioGroup1_0" />
男 </label>
<label>
<input type="radio" name="RadioGroup1" value="单选" id="RadioGroup1_1" />
女</label>
<br />
</p></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">归属地:</td>
<td height="30"><label for="select"></label>
<select name="select" id="select">
<option>北京</option>
<option>天津</option>
<option>上海</option>
<option>浙江</option>
<option>山东</option>
<option>山西</option>
<option>重庆</option>
</select></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">电子邮箱:</td>
<td height="30"><label for="textfield19"></label>
<input type="text" name="textfield2" id="textfield19" /></td>
</tr>
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<td width="120" height="30" align="right" valign="middle">QQ号码:</td>
<td height="30"><label for="textfield20"></label>
<input type="text" name="textfield3" id="textfield20" /></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">标题:</td>
<td height="30"><label for="textfield21"></label>
<input type="text" name="textfield4" id="textfield21" /></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">正文:</td>
<td height="30"><label for="textarea"></label>
<textarea name="textarea" id="textarea" cols="45" rows="5"></textarea></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle">头像:</td>
<td height="30"><label for="fileField"></label>
<input type="file" name="fileField" id="fileField" /></td>
</tr>
<tr>
<td width="120" height="30" align="right" valign="middle"> </td>
<td height="30"><input type="submit" name="button" id="button" value="提交" />
<input type="reset" name="button2" id="button2" value="重置" /></td>
</tr>
</tbody>
</table>
</form></td>
</tr>
</tbody>
</table></td>
</tr>
</table>
</body>
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