STEP 1
Login to Pretashop admin area > Localization
Localization pack you want to import > Choose your package
Download pack data > Yes
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STEP 2
Click International > Translations > Add / Update a language
Please select the language you want to add > Select language and then click add or update language button
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Go to Localization > Language and make sure the language you have just added is already there
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STEP 3
Go to International > Translation >Modify Languages
Type of translation > Theme Translations
Select your theme > Your theme
Select your language > Language
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