Plesk apres reinstallation crash

[Rebastian]

Good evening,
I needed to re-install Plesk apres a crash with the command apt-get install --reinstall psa.

Usually it works well, but the apres the reinstallation I connect me has plesk and here is the message which I obtain:

ERROR: PleskFatalException
Unable to get default language.

0: /opt/psa/admin/plib/common_func.php3:156
psaerror(string 'Unable to get default language.')
1: /opt/psa/admin/plib/countries.php3:293
locale_list()
2: /opt/psa/admin/plib/common_func.php3:1604
locale_exists(string 'fr-FR')
3: /opt/psa/admin/plib/class.Session.php:167
Session->Session()
4: /opt/psa/admin/auto_prepend/auth.php3:157

You can give me a solution, it is rather urgent.
Saddened for English.

Cordially.