Problem solved : I deleted an old NLS_LANG variable in Windows environment It certainly overwriting the ODVD setting default. Thanks for the time

Salutare Gianni Yes both DVD and XE18c same PC I reinstall the latest version of DVD and set you the logs (C:\Users\soutou\AppData\Local\Temp\DVDesktop\logs\OBIS\obis1-diagnostic.log) after attempt a connection

Hi Gianni, Thanks I tried with XE CDB and XEPDB1 as PDB, the problem still exists I read Oracle MOS document relating to this error message "Error ORA-12705: Cannot access NLS data files or invalid environment specified", they advise to delete or rename NLS_LANG in Windows registry See the pdf joined, the sql+ test, the…