"The detected language does not match that expected by the project" problem

Dear Community,

 

 I have a project at hand sent by customer to me. The Trados Package includes  files with some kinds of MemoQ file types that they have a extention as "mqxlz" .

I click on them to open and translate in editor, but it is impossible to process, a screen comes out as below.

Actually, to solve this problem I checked the file types from the Project Settings, and  I saw that the ".mqxlz" files are already checked and allowed..

So, after all these, what can I do to make it possible to process these files? I am really confused..

 Thank you so much for your assistance..

 Best Regards ,

Bahar