One question about VACUUMDB command - please

Dear Sirs,
I'm trying to put some scipt into scheduler on my server 2000 to make auto
vacuum one time in mouth.
Why this comand that I write belove ask me for password, even I create user
into DB with same password like user on my server that execute this
command?

Can you suggest me some other solutions?

C:\>vacuumdb --host=3D127.0.0.1 --full --dbname=3Dpostgres

Thanks,
Best Regards,
Sasa Petrovic
Sistemi Informativi
Falc East - Knjazevac
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