Can't access LibreELEC from Windows

Trying to access LibreELEC 9.0.0 from a Windows 10 machine.
According to information found here, username and password for access are both "libreelec".
When Windows presents the authentication window and I enter both, it accepts "libreelec" as as a legitimate username but continue to ask for password.

Tried just in case to enable SMB v1 both on LibreELEC and Windows but no way.
What am I doing wrong?

Will try that.
Wanted to search for the file that contains the library to edit it manually.

That's because I noted a number of duplicates that wouldn't go away.
Decide to start from zero, so changed all contents to NONE and them to MOVIE.
However, one single movie stubbornly remained.

Decided then to export the library and it was entirely empty, thus meaning that the single movie that remained should be due to another problem.