Codeigniter Validation errors work on localhost not on server - codeigniter

Question

I have problem same code running on local and on server, but i dont get validation errors when i upload code online. I pass validatio errors via flashdata
Controller
function send_mail($lang)
{
$this->load->library(array('email','form_validation'));
$this->form_validation->set_rules('fullname', 'Full Name','trim|required|xss_clean');
$this->form_validation->set_rules('address', 'Permanent Home Address', 'trim|required|xss_clean');
$this->form_validation->set_rules('posta', 'Email Address', 'required|valid_email|xss_clean');
$this->form_validation->set_rules('country', 'Country of Citizenship', 'trim|required|xss_clean');
$this->form_validation->set_rules('date', 'Date of Birth','trim|required|xss_clean');
$this->form_validation->set_rules('tel', 'Telephone Number','trim|required|xss_clean');
$this->form_validation->set_rules('inst', 'Name of Institution','trim|required|xss_clean');
$this->form_validation->set_rules('study', 'Field of Study', 'trim|required|xss_clean');
$this->form_validation->set_rules('degree', 'Degree awarded/expected','trim|required|xss_clean');
$this->form_validation->set_rules('dates1', 'Dates attended', 'trim|required|xss_clean');
$this->form_validation->set_rules('dates2', 'Dates attended', 'trim|required|xss_clean');
$this->form_validation->set_rules('employment', 'Employment', 'trim|required|xss_clean');
$this->form_validation->set_rules('language', 'Language Skills', 'trim|required|xss_clean');
$this->form_validation->set_rules('statement', 'Statement', 'trim|required|xss_clean');
if($this->form_validation->run()==FALSE)
{
$this->session->set_flashdata('errors', validation_errors());
$this->set_fleshdata();
header('Location: '.$_SERVER['HTTP_REFERER']);
}
else
in view
<?php
$this->load->helper(array('form', 'url'));
$this->load->library('form_validation');
$attributes = array('id' => 'intership_application_form',
'name' => 'intership',
);
echo $this->session->flashdata('success');
echo form_open_multipart('pages/send_mail/'.$lang, $attributes);
?>
<section>
<div > All fields required, only files in doc, docx or pdf format are allowed.</div><br/>
<div class="form_item">
<label class="form_item_name">Full Name:</label>
<input type="text" name="fullname" placeholder="Full Name" value="<?php echo $this->session->flashdata('name'); ?>" >
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Permanent Home Address:</label>
<input type="text" name="address" placeholder="Permanent Home Address" value="<?php echo $this->session->flashdata('address'); ?>"/>
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Email Address:</label>
<input type="email" name="posta" placeholder="Email Address" value="<?php echo $this->session->flashdata('posta'); ?>"/>
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Country of Citizenship:</label>
<input type="text" name="country" placeholder="Country of Citizenship" value="<?php echo $this->session->flashdata('country'); ?>" />
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Date of Birth:</label>
<input type="text" name="date" placeholder="Date of Birth" value="<?php echo $this->session->flashdata('date'); ?>" />
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Telephone Number:</label>
<input type="text" name="tel" placeholder="Telephone Number" value="<?php echo $this->session->flashdata('tel'); ?>"/>
</div><!--end .form_item-->
</section>
<section>
<p><strong>University Level Education</strong> <span>[ Please give details of your final school leaving qualification ]</span></p>
<div class="form_item">
<label class="form_item_name">Name of Institution:</label>
<input type="text" name="inst" placeholder="Name of Institution" value="<?php echo $this->session->flashdata('inst') ?>"/>
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Field of Study:</label>
<input type="text" name="study" placeholder="Field of Study" value="<?php echo $this->session->flashdata('study'); ?>"/>
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Degree awarded/expected:</label>
<input type="text" name="degree" placeholder="Degree awarded/expected" value="<?php echo $this->session->flashdata('degree'); ?>"/>
</div><!--end .form_item-->
<div class="form_item">
<label class="form_item_name">Dates attended:</label>
<input type="text" name="dates1" placeholder="Dates attended" value="<?php echo $this->session->flashdata('dates1'); ?>" />
<input class="below" type="text" name="dates2" placeholder="Dates attended" value="<?php echo $this->session->flashdata('dates2'); ?>"/>
</div><!--end .form_item-->
</section>
<section class="third">
<div class="form_item">
<label class="form_item_name" />Employment<span>[ Please outline details of employment history or relevant professional experience ]</span></label>
<textarea cols="" rows="" name="employment" placeholder="Your text here" ><?php echo $this->session->flashdata('employment'); ?></textarea>
</div>
<div class="form_item">
<label class="form_item_name" />Language SKills:<span>[ Proficiency in English is required for all CIRSD internship applicants, who are encouraged to indicate knowledge of any additional languages ]</span></label>
<textarea cols="" rows="" name="language" placeholder="Your text here" ><?php echo $this->session->flashdata('language'); ?></textarea>
</div>
</section>
<section class="third">
<div class="form_item">
<label class="form_item_name">References:<span>[Please include three academic/professional references or letters of recommendation ]</span></label>
<div class="right">
<p>Please attach your reference here:</p>
<div class="upload_buttons">
<p class="form">
<input type="text" id="path" class="path" />
<label class="add-photo-btn">BROWSE<span><input type="file" id="myfile" name='file1' /></span>
</label>
</p>
<p class="form">
<input type="text" id="path1" class="path" />
<label class="add-photo-btn">BROWSE<span><input type="file" id="myfile1" name='file2' /></span>
</label>
</p>
<p class="form">
<input type="text" id="path2" class="path" />
<label class="add-photo-btn">BROWSE<span><input type="file" id="myfile2" name='file3' /></span>
</label>
</p>
</div><!--end .upload_buttons-->
</div><!--end .form_item-->
</section><!--end .third-->
<section class="third">
<div class="form_item">
<label class="form_item_name" />Personal Statement:<span>[ Compose a brief personal statement in English outlining your interests, why you are applying for the CIRSD internship program, and what you hope to gain from it. Include an explanation of what makes you a suitable candidate for an internship at CIRSD. All statements should not exceed the limit of 750 words ]</span></label>
<textarea name="statement" cols="" rows="" class="personal_statement" placeholder="Your text here"><?php echo $this->session->flashdata('statement'); ?></textarea>
</div>
<div class="form_item cv">
<label class="form_item_name" />Cirriculum Vitae:</label>
<div class="right cv">
<p class="form">
<input type="text" id="path3" class="path cv" value="Please attach your CV here:" />
<label class="add-photo-btn">BROWSE<span><input type="file" id="myfile3" name='file4' multiple /></span>
</label>
</p>
</div>
</div>
</section><!--end .third-->
<section class="third">
<div class="form_item spam">
<label>Spam Check:</label>
<div class="spam_form">
<img src="<?php echo site_url(); ?>captcha_code_file.php?rand=<?php echo rand(); ?>" name="6_letters_code" id='captchaimg' >
<input type="text" class="spam_input" name="6_letters_code"/>
<input type="submit" class="send_btn" value="SEND" id="button"/>
</div>
</div><!--end .form_item-->
</section><!--end .third-->
<?php form_close(); ?>
<div><?php var_dump($this->session->flashdata('errors'));?></div>
Last line is important. Strange why my code works on xampp not on live server?

Answer 1

Please check your code you are setting 'errors' variable for setting errors messages and on view part you are accessing 'success' variable. Please use same variable at both places.
Controller:
$this->session->set_flashdata('errors', validation_errors());
View:
echo $this->session->flashdata('success');
And what is use of this function in controller $this->set_fleshdata(); the above method (set_flashdata) is enough to set your flashdata.
Also in the last line you forgot to write 'echo' before the form
<?php form_close(); ?> should be <?php echo form_close(); ?>