Kumi, can you please truncate ow_newsfeed_action_set table as well?

Now you have this error: 

you need to repair this table 

ow_newsfeed_action_set table is empty.

I just checked

see my post above

Repairing the table is beyond my skills now. If you can do that for me.

Okay. Thanks

If it doesn't work out, how about uploading a database I saved before the update?

If you mean back up, you're free to do that. Import it via phpmyadmin and change access attributes in the config.php file. 

Can you see the site now and tell me what's happening? I repaired the table but I still see this.

Screenshot please. 

Here They are

Contact plugin developer of the top users to resolve your issue. Errors are caused by this plugin

I have deleted it and now I have this problem.
If I type www.bookerzmedia.com, this is what I get below;
Warning: Unterminated comment starting line 90 in /home/bookerzm/public_html/ow_core/validator.php on line 90

If I type www.bookerzmedia.com, the sign-in page opens with no error but when I sign in, this is what I get below;
Fatal error: Cannot redeclare class OW_Validator in /home/bookerzm/public_html/ow_core/validator.php on line 33

Below is the entire page for the entire validator.php, Can you check what is wrong with it?
Thanks
<?php

/**
 * EXHIBIT A. Common Public Attribution License Version 1.0
 * The contents of this file are subject to the Common Public Attribution License Version 1.0 (the “License”);
 * you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.oxwall.org/license. The License is based on the Mozilla Public License Version 1.1
 * but Sections 14 and 15 have been added to cover use of software over a computer network and provide for
 * limited attribution for the Original Developer. In addition, Exhibit A has been modified to be consistent
 * with Exhibit B. Software distributed under the License is distributed on an “AS IS” basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language
 * governing rights and limitations under the License. The Original Code is Oxwall software.
 * The Initial Developer of the Original Code is Oxwall Foundation (http://www.oxwall.org/foundation).
 * All portions of the code written by Oxwall Foundation are Copyright (c) 2011. All Rights Reserved.

 * EXHIBIT B. Attribution Information
 * Attribution Copyright Notice: Copyright 2011 Oxwall Foundation. All rights reserved.
 * Attribution Phrase (not exceeding 10 words): Powered by Oxwall community software
 * Attribution URL: http://www.oxwall.org/
 * Graphic Image as provided in the Covered Code.
 * Display of Attribution Information is required in Larger Works which are defined in the CPAL as a work
 * which combines Covered Code or portions thereof with code not governed by the terms of the CPAL.
 */

/**
 * Base validator class.
 *
 * @author Sardar Madumarov <madumarov@gmail.com>
 * @package ow_core
 * @since 1.0
 */
abstract class OW_Validator
{
    /**
     * Error message.
     *
     * @var string
     */
    protected $errorMessage;

    /**
     * Checks if provided value is valid.
     *
     * @param mixed $value
     * @return boolean
     */
    abstract function isValid( $value );

    /**
     * Returns validator error message.
     *
     * @return string
     */
    public function getError()
    {
        return $this->errorMessage;
    }

    /**
     * Sets validator error message.
     *
     * @param string $errorMessage
     * @return OW_Validator
     * @throws InvalidArgumentException
     */
    public function setErrorMessage( $errorMessage )
    {
        if ( $errorMessage === null || mb_strlen(trim($errorMessage)) === 0 )
        {
            //throw new InvalidArgumentException('Invalid error message!');
            return;
        }

        $this->errorMessage = trim($errorMessage);
    }

    /**
     * Returns validator js object code.
     *
     * @return string
     */
    public function getJsValidator()
    {
        return "{
            validate : function( value ){}
        }";
    }
}

/**
 *

I saw something wrong.
define('OW_DEBUG_MODE', false); false was written as fales

The file is not complete, download the original package and replace the files. 

Also some plugin tries to use the class which is declared in the core software, disable all 3rd party plugins one-by one and see if the error persists. 

I did that,
If I go straight to www.bookerzmedia.com, it opens well with no errors. Then I sign in, I the error that
Fatal error: Cannot redeclare class OW_Validator in /home/bookerzm/public_html/ow_core/validator.php on line 33

Since I don't have some different script, I can't compare the difference on line 33. I downloaded and replaced the validator.php today. I don't have the old one.

I can't go to admin to disable the plugins

I told you to replace the file. 

Why did not you? 

I just replaced it and now it opens. Please be more attentive to the instructions. 

Yes,
I have a custom sign in page. I am using http://www.oxwall.org/store/item/601
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