Internal Error when looking at a product

-- url of the page with the problem -- : cherrycosmetics.com.au
-- HikaShop version -- : 2.3.4
-- Joomla version -- : 3.3.6
-- PHP version -- : 5.3.28
-- Browser(s) name and version -- : Google Chrome
-- Error-message(debug-mod must be tuned on) -- : Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, This email address is being protected from spambots. You need JavaScript enabled to view it. and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 500 Internal Server Error error was encountered while trying to use an ErrorDocument to handle the request.

Everything seems to work fine, but as soon as you look at a product on the front end both front and back ends display the 500 Internal error message.

I have to clear my browsing history to reload it - this only just started happening out of the blue and I haven't changed any of my settings on my Internet Browser. I was just adding products and building the website and bam! it started doing this

I have tried everything listed on all the forums I can find but can't see anything odd.

I have debug on and error reporting on maximum but I don't understand what it is saying.

Please help!!!

This is going to sound stupid but how do I find the right error log? Is this through myPHPadmin / cPanel or via FTP?

In cPanel this is all I get in the error log: (it's repeated)

[Mon Nov 17 10:04:27 2014] [alert] [client *MY IP ADDRESS*] /home/*USERNAME*/public_html/.htaccess: Invalid command 'php_value', perhaps misspelled or defined by a module not included in the server configuration

via FTP the last entries on the error log are:

[17-Nov-2014 19:12:10 Australia/Melbourne] PHP Notice: Undefined property: stdClass::$prices in /home/*USERNAME*/public_html/components/com_hikashop/views/category/view.feed.php on line 180

[17-Nov-2014 19:12:10 Australia/Melbourne] PHP Notice: Trying to get property of non-object in /home/*USERNAME*/public_html/components/com_hikashop/views/category/view.feed.php on line 180

Do any of these help?

At the moment all your pages return error 500.

Do you have any php_value directives in .htaccess?

# Begin - Joomla! core SEF Section.
#
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
#
# If the requested path and file is not /index.php and the request
# has not already been internally rewritten to the index.php script
RewriteCond %{REQUEST_URI} !^/index\.php
# and the request is for something within the component folder,
# or for the site root, or for an extensionless URL, or the
# requested URL ends with one of the listed extensions
RewriteCond %{REQUEST_URI} /component/|(/[^.]*|\.(php|html?|feed|pdf|vcf|raw))$ [NC]
# and the requested path and file doesn't directly match a physical file
RewriteCond %{REQUEST_FILENAME} !-f
# and the requested path and file doesn't directly match a physical folder
RewriteCond %{REQUEST_FILENAME} !-d
# internally rewrite the request to the index.php script
RewriteRule .* index.php [L]
#
## End - Joomla! core SEF Section.

Is this what you mean? - it's from the htaccess.txt file

[Mon Nov 17 10:04:27 2014] [alert] [client *MY IP ADDRESS*] /home/*USERNAME*/public_html/.htaccess: Invalid command 'php_value', perhaps misspelled or defined by a module not included in the server configuration

This error means that you have php_value statement in .htaccess, but it's not allowed by your server configuration.
You can use php_value in .htaccess only, when your server is executing php using mod_php.

Try to locate php_value statements in .htaccess and comment them out, or rename .htaccess to htaccess.old and then renaming htaccess.txt to .htaccess

I commented it out, it still goes to Internal error when adding something to the cart - so I renamed it as suggested.
Now the whole site is Internal Error again.

I have tried the above suggestion a few times now as after Google search on the issue it was a common fix but it's not working for me

Here is the full file - htaccess.txt (now renamed to htaccess.old)
##
# @package Joomla
# @copyright Copyright (C) 2005 - 2014 Open Source Matters. All rights reserved.
# @license GNU General Public License version 2 or later; see LICENSE.txt
##

##
# READ THIS COMPLETELY IF YOU CHOOSE TO USE THIS FILE!
#
# The line just below this section: 'Options +FollowSymLinks' may cause problems
# with some server configurations. It is required for use of mod_rewrite, but may already
# be set by your server administrator in a way that dissallows changing it in
# your .htaccess file. If using it causes your server to error out, comment it out (add # to
# beginning of line), reload your site in your browser and test your sef url's. If they work,
# it has been set by your server administrator and you do not need it set here.
##

## Can be commented out if causes errors, see notes above.
#Options +FollowSymLinks

## Mod_rewrite in use.

RewriteEngine On

## Begin - Rewrite rules to block out some common exploits.
# If you experience problems on your site block out the operations listed below
# This attempts to block the most common type of exploit `attempts` to Joomla!
#
# Block out any script trying to base64_encode data within the URL.
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
# Block out any script that includes a <script> tag in URL.
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
# Block out any script trying to set a PHP GLOBALS variable via URL.
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block out any script trying to modify a _REQUEST variable via URL.
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
# Return 403 Forbidden header and show the content of the root homepage
RewriteRule .* index.php [F]
#
## End - Rewrite rules to block out some common exploits.

## Begin - Custom redirects
#
# If you need to redirect some pages, or set a canonical non-www to
# www redirect (or vice versa), place that code here. Ensure those
# redirects use the correct RewriteRule syntax and the [R=301,L] flags.
#
## End - Custom redirects

##
# Uncomment following line if your webserver's URL
# is not directly related to physical file paths.
# Update Your Joomla! Directory (just / for root).
##

# RewriteBase /

## Begin - Joomla! core SEF Section.
#
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
#
# If the requested path and file is not /index.php and the request
# has not already been internally rewritten to the index.php script
RewriteCond %{REQUEST_URI} !^/index\.php
# and the request is for something within the component folder,
# or for the site root, or for an extensionless URL, or the
# requested URL ends with one of the listed extensions
RewriteCond %{REQUEST_URI} /component/|(/[^.]*|\.(php|html?|feed|pdf|vcf|raw))$ [NC]
# and the requested path and file doesn't directly match a physical file
RewriteCond %{REQUEST_FILENAME} !-f
# and the requested path and file doesn't directly match a physical folder
RewriteCond %{REQUEST_FILENAME} !-d
# internally rewrite the request to the index.php script
RewriteRule .* index.php [L]
#
## End - Joomla! core SEF Section.


And this is the .htaccess file:
##
# @package Joomla
# @copyright Copyright (C) 2005 - 2014 Open Source Matters. All rights reserved.
# @license GNU General Public License version 2 or later; see LICENSE.txt
##

##
# READ THIS COMPLETELY IF YOU CHOOSE TO USE THIS FILE!
#
# The line just below this section: 'Options +FollowSymLinks' may cause problems
# with some server configurations. It is required for use of mod_rewrite, but may already
# be set by your server administrator in a way that dissallows changing it in
# your .htaccess file. If using it causes your server to error out, comment it out (add # to
# beginning of line), reload your site in your browser and test your sef url's. If they work,
# it has been set by your server administrator and you do not need it set here.
##

## Can be commented out if causes errors, see notes above.
Options +FollowSymLinks

## Mod_rewrite in use.

RewriteEngine On

## Begin - Rewrite rules to block out some common exploits.
# If you experience problems on your site block out the operations listed below
# This attempts to block the most common type of exploit `attempts` to Joomla!
#
# Block out any script trying to base64_encode data within the URL.
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
# Block out any script that includes a <script> tag in URL.
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
# Block out any script trying to set a PHP GLOBALS variable via URL.
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block out any script trying to modify a _REQUEST variable via URL.
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
# Return 403 Forbidden header and show the content of the root homepage
RewriteRule .* index.php [F]
#
## End - Rewrite rules to block out some common exploits.

## Begin - Custom redirects
#
# If you need to redirect some pages, or set a canonical non-www to
# www redirect (or vice versa), place that code here. Ensure those
# redirects use the correct RewriteRule syntax and the [R=301,L] flags.
#
## End - Custom redirects

##
# Uncomment following line if your webserver's URL
# is not directly related to physical file paths.
# Update Your Joomla! Directory (just / for root).
##

# RewriteBase /

## Begin - Joomla! core SEF Section.
#
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
#
# If the requested path and file is not /index.php and the request
# has not already been internally rewritten to the index.php script
RewriteCond %{REQUEST_URI} !^/index\.php
# and the requested path and file doesn't directly match a physical file
RewriteCond %{REQUEST_FILENAME} !-f
# and the requested path and file doesn't directly match a physical folder
RewriteCond %{REQUEST_FILENAME} !-d
# internally rewrite the request to the index.php script
RewriteRule .* index.php [L]
#
## End - Joomla! core SEF Section.

<Files 403.shtml>
order allow,deny
allow from all
</Files>

deny from 146.0.73.134/5

(The deny from Ip address is one used to hack the site previously)

I'm really stressing out over this website, please tell me there's a simple error here that can be an easy fix

Backup your .htaccess file for reference and delete it.
Check your site if it's working. All links except homepage will be 404.
Then copy htaccess.txt from Joomla installation package to server and rename it to .htaccess (I attached htaccess.txt from Joomla 3.3.6). Don't modify it.

If site is again 500, check log in cPanel and post errors here.

Ok, have done - Checked the site and it still has the error on add to cart and then the whole site crashes.

Error Log in cPanel:

[Wed Nov 19 11:02:32 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:02:32 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/info-faq-s, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:02:28 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:02:28 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/info-faq-s, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:00:33 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:00:33 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/shop-online, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:00:29 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml
[Wed Nov 19 11:00:29 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/favicon.ico
[Wed Nov 19 11:00:29 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:00:29 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/info-faq-s, referer: cherrycosmetics.com.au/
[Wed Nov 19 11:00:28 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/404.shtml
[Wed Nov 19 11:00:28 2014] [error] [client 139.130.224.79] File does not exist: /home/MYUSERNAME/public_html/component
[Wed Nov 19 08:59:38 2014] [error] [client 144.76.95.39] client denied by server configuration: /home/MYUSERNAME/public_html/index.php
[Wed Nov 19 08:59:38 2014] [error] [client 144.76.95.39] client denied by server configuration: /home/MYUSERNAME/public_html/robots.txt
[Wed Nov 19 07:12:49 2014] [error] [client 144.76.8.132] client denied by server configuration: /home/MYUSERNAME/public_html/index.php
[Wed Nov 19 07:12:49 2014] [error] [client 144.76.8.132] client denied by server configuration: /home/MYUSERNAME/public_html/robots.txt

How frustrating - P.S I appreciate all of your help so far!

Was site without .htaccess working?
Could you post also php error log?

Also feel free to pm me your skype/google talk.

Without it yes, as you said home page was fine and links 404.

php error log - which one is that? I can't see any logs in phpmyadmin

Thanks so much for all of your help!

Error was caused by the template in font adjustment - Thanks Korzo!!!