Site Interface with error after upgrade from 5.7.3 into

I just updated my concrete5 from 5.7.3 into and then into The upgrade shows success message. What i found not working is the multilingual's translate interface. When I click on the edit button for a language it display the error
The method setPluralForms does not exists
. When i try to click on reload strings it show the error page with
Call to undefined method Gettext\Translation::getExtractedComments()

Any idea?

View Replies:
mlocati replied on at Permalink Reply
It's really strange.

It seems that your setup is loading code from an older version of the vendor dir...
jtay replied on at Permalink Reply
Thanks for the reply, I solved it by using another upgrade option which is replacing my old /concrete with the new /concrete.