Solved Kunena 5.0.1 language strings problem (COM_KUNENA_X_TOPICS etc)

Hi,
I have Joomla 3.6.2, Kunena 5.0.1 and all plugins / language pack etc updated to the latest version.

I use wamp 3.0.0 as test enviroment with php 5.6.16.

The problem is that a lot of specific strings in forum are shown as COM_KUNENA_TOPIC_STARTED_ON, COM_KUNENA_X_TOPICS_MORE etc instead of the correct words or numbers they should write.

In configuration the option "Use English On Missing Strings" is set to Yes but it still appears the COM_KUNENA etc instead of the correct words.

I use Greek language in the forum, and even if I disable the Greek language from extensions / manage/ manage / Kunena Language - Greek (Greece) the problem is still the same.
Only if I uninstall completely the Greek language then the forum use in these strings the English language correctly. If I try to install again the language pack then the problem appears again with the wrong strings (COM_KUNENA_X_TOPICS_MORE etc)

I had the same problem when I updated in Wamp the kunena forum from 4 to 5.0 but I had read somewhere here in forum that this bug would be fixed in 5.0.1 but the problem is still exist after I updated to 5.0.1..

I tried a lot of things like to clear cache / expired cache, I uninstalled / reinstalled the language pack 5.0.1 and kunena itself, clear cookies in browser, changed PHP version in wamp from 5.6.16 to 7.0.0 but still the same.

Is there a fix for this "bug" because I cannot update to 5.0.1 in the live site if I have this problem and I have still the version 4 of kunena...

Thank you very much for your time.

Hello. My solution..

remove
COM_KUNENA_X_TOPICS_0 = "No topics"
COM_KUNENA_X_TOPICS_1 = "%s tppics"

write
COM_KUNENA_X_TOPICS = "%s topics"

It works.

Do you guys have installed the kunena language pack? because for me its works: I can see the English strings

Of course, it is installed.

ok, see the issue.

please copy all the content from components\com_kunena\language\en-GB to language\en-GB

Ok, fixed, check updater