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Your LimeSurvey version: Version 5.2.13+220207
Own server or LimeSurvey hosting:
Survey theme/template: datacentrum
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I have stuck on this last step found here:  www.limesurvey.org/manual/Translating_LimeSurvey
6. The last step is to place the particular *.mo file in the right language folder in /locale by replacing the existing one. 

Can anyone explain where should I put the *.mo file. I cannot seem to find a place to replace the old file with the new one. 

Thank you in advance whether you help or not.

If you only replace an existing one you put it into the folder with the same name as the *.mo file.
If the *.mo file is "mya.mo" you put it into the folder "mya".

 

Thank you for your quick reply.

My file is *.mo. It may seem like a dumb question but where is the folder.
I exported the language from here translate.limesurvey.org/projects/
and edited it with poedit and the file *.mo is crerated now I do not know where to put this file.

But once you downloadfad a file
 

with a name like this
 

This is finnish.
And as you see in the "/locale" folder "fi" there is a file "fi.mo"

I do not have PoEdit installed on this machine, but if you save your new translation you are asked for a filename.
So you might rename your *.mo file to something like "[language code].mo"
 

My edited translation is saved with the language code by the app poedit. What should I do with this file. Is this wehre I should insert the file?(secpnd picture) In the first picture the first one is the *.mo file

My edited translation is saved with the language code

If it is saved with the language code, again

If the *.mo file is "mya.mo" you put it into the folder "mya".

If the *.mo file is "it.mo" you put it into the folder "it".
In general, the "[language code].mo" you put into the folder "[language code]"

it with poedit and the file *.mo is crerated

You need to rename that file, replacing the star with the appropriate language code. Then place it in the same locale file.

Thank you for your replies, I renamed the file just as you suggested but I still cannot find the locale file or folder where I can insert my sq.mo file. Where are the folders with the respective language codes? Are they here translate.limesurvey.org/projects/ ?

The folders are on your server where LimeSurvey is installed.