Change language via pot / .po / .mo

Hello,
i trying to change the language via .po file. I placed my .po and .mo files under wp-content/plugins/cmsmasters-contact-form-builder/languages and the are called
de_DE.mo and de_DE.po
How should i call the file to make the translation working and where do I have to place them?

I already tried this method (with no success – also after reloading my page):
https://web-dorado.com/forum/26-form-maker/14447-how-to-change-language-of-form-maker-in-wordpress.html

Thank you.
with warm regards
Sebastian

• This topic was modified 8 years, 2 months ago by sreservices.