Fatal error: Call to undefined function wp() in wp-blog-header.php

Hi,

I’m a novice and I need your help to resolve a problem with my new site.

I tried to change wordpress language in french manually installing language files as described in WordPress Codex.
After the changes I got 500 Internal Server Error when trying to access my front site and wp admin.

Then I deleted the language folder I had created in wp-content and the code for french language I had put in wp-config.php file. I reuploaded the wp-config file. Nothing has changed. Still have the same error message.

Here is a link to my site http://www.penseespositives.com/

In my public_html folder I saw an error_log file with the following messages:

04-Mar-2013 09:08:56] PHP Parse error: syntax error, unexpected T_STRING in /home8/penseesp/public_html/wp-content/thesis/skins/classic/custom.php on line 19

[14-Mar-2013 08:22:50] PHP Fatal error: Call to undefined function wp() in /home8/penseesp/public_html/wp-blog-header.php on line 14

I guess it is the second error that caused the major problem.

I’m not sure, but I think I made a mistake editing wp_config.php file using WordPad.

I checked the support forum, but I was lost reading all the possible causes and solutions of this kind of problem. I don’t want to make more demages so I hope you can help me find a solution.

Do you have an idea what exactly caused the error and how to fix it?

Thank you very much for your time!

Regards,
Tsveti