Piwik language error

Hey guys,
First I want to say, Piwik is a very cool web analytics software.

I have been a user for a very long time, and today I finally decided to upgrade my software to the latest version.

Unfortunately now I’m getting this error which I copy pasted below:

The language selected (’’) is not a valid language file
Backtrace:
#0 /home/blablabla/public_html/piwik/core/Translate.php(43): Piwik_Translate->getLanguageToLoad()
#1 /home/blablabla/public_html/piwik/core/FrontController.php(236): Piwik_Translate->loadUserTranslation()
#2 /home/blablabla/public_html/piwik/index.php(51): Piwik_FrontController->init()
#3 {main}
• Piwik homepage
• Piwik demo

Do you guys have any solutions for this problem? I did check the FAQ.

Thanks a lot.

Okay, I got it fixed already. I had to upload the files in the config folder as well. I did that, changed the details and it’s working now. (all thanks to a friend as well)