Hi all,
I'd just like to share that one - in case someone else runs into the same issue.
I just created a new db schema on the customers autonomous data warehouse using a complex password but no special characters.
create user username identified by G48GHoJSKrb5hB;
Then I tried to login in and got ORA-01017: invalid username/password.
Solution in my case was to use a password with at least two special characters. After that, the login succeeded.
Best regards
Michael