SOLVED!
I made some "housekeeping" using, as recommended, a solution more cloud oriented, sync based. That didn't solve my problem, but make the system more robust.
The problem was with the setting of the environment variables (EV).
On my "server", there is 2 accounts: Admin and Calibre.
Admin has the administrator rights, not Calibre. When trying to set the EV on Calibre, I used this way:
https://kb.wisc.edu/cae/page.php?id=24500
The account Calibre not beeing "Admin", the system asks for the admin autorisation, asking for the Admin's password. What I finally discovered is that by doing that, the EV is not extended to the Calibre account.
The right way of creating the EV in the Calibre account was to go to:
Code:
Control Panel\User Accounts and Family Safety\User Accounts
and use the item "Change my environment variables" from the menu.
Thanks,
GH