Small update : I uninstalled and reinstalled SDL. It opened properly but none on my Language Cloud projects were visible.

When I connected to my account, it crashed down again with the same issue

 Laetitia ZUMSTEIN 

Make sure you are signed into Studio, and also check your filters in the navigation pane of the Projects View.

I once uninstalled it, reinstalled it, got signed in and then it crashed.

Now, I uninstalled it, reinstalled it and do not even manage to open it without having the same view

Laetitia ZUMSTEIN 

Try a reset and if that doesn't work I'll log a case for you.  To do this just close Trados Studio and then rename this folder:

c:\Users\%username%\AppData\Roaming\Trados\Trados Studio\Studio17\

to c:\Users\%username%\AppData\Roaming\Trados\Trados Studio\Studio17_old\

If you can't find this folder then you need to unhide your hidden files/folders:

www.howtogeek.com/.../

Then restart Trados Studio and see if that helped.