Setlocale returns false (WAMP)
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I have working localization in my project. Working means, my project gets translated to whatever language I have in the locale/sk folder, sk for slovak being my default system language

Setting to any other language doesn't work. I have tried $lang = 'cs', 'cz', 'en', 'en_UK', 'en_UK.utf8' and other. Still only translation in 'sk' folder is taken and still the setlocale() function returns false. I have tried to change default language in browser - no effect. 

This is my code:
   
    putenv("LANG=$lang"); 
    setlocale(LC_ALL, $lang); 
    bindtextdomain("messages", realpath("../localem")); 
    textdomain("messages");

I have also tried these

    putenv("LANGUAGE=$lang"); 
    putenv('LC_ALL=$lang');

Any suggestions are welcome.