yii show error 404 Unable to resolve the request "js/ajaxuploadcarphotomain.php"

I web works fine previously until yesterday I get this error on my image upload function.

Error 404
Unable to resolve the request "js/ajaxuploadcarphotomain.php"

but when i manually access to the link, the page returns result 'File size is too big'.

<script type="text/javascript" src="<?php echo Yii::app()->request->baseUrl; ?>/js/ajaxupload.js"></script>
<form action="js/ajaxuploadcarphotomain.php" method="post" name="sleeker" id="sleeker" enctype="multipart/form-data">
        <input type="hidden" name="maxSize" value="3000000" />
        <input type="hidden" name="maxW" value="800" />
        <input type="hidden" name="fullPath" value="images/carphoto/" />
        <input type="hidden" name="relPath" value="../images/carphoto/" />
        <input type="hidden" name="colorR" value="255" />
        <input type="hidden" name="colorG" value="255" />
        <input type="hidden" name="colorB" value="255" />
        <input type="hidden" name="maxH" value="600" />
        <input type="hidden" name="filename" value="filename" />
        <p><input id="id_car_main_photo" class="btn-link" type="file" name="filename" onchange="ajaxUpload(this.form,'<?php echo Yii::app()->request->baseUrl; ?>/js/ajaxuploadcarphotomain.php?filename=name&amp;maxSize=3000000&amp;maxW=800&amp;fullPath=images/carphoto/&amp;relPath=../images/carphoto/&amp;colorR=255&amp;colorG=255&amp;colorB=255&amp;maxH=600','upload_area','File Uploading Please Wait...&lt;br /&gt;&lt;img src=\'../images/loader_light_blue.gif\' width=\'128\' height=\'15\' border=\'0\' /&gt;','&lt;img src=\'images/error.gif\' width=\'16\' height=\'16\' border=\'0\' /&gt; Error in Upload, check settings and path info in source code.'); return false;" /></p>
</form>

what is the root cause for this issue?

My .htaccess

RewriteEngine on

# if a directory or a file exists, use it directly
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

# otherwise forward it to index.php
RewriteRule . index.php

Directory

css
protected
js
.htaccess

I cannot access www.example.com/js but http://ift.tt/1KHgFPw can