title: how to connect to local oracle database 19c using sysdba
body: <p>i have install oracle 19c in my PC, but when i want to connect using SQL Plus i cannot login. i got error like this
  the error is like my password wrong or cannot open.</p>
  <p><a href="https://i.stack.imgur.com/ncslh.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ncslh.png" alt="error when try using Default password" /></a>
  when i install the installer not require password. when i try to use default password as password i got error. so how to fix my problem here ?? i have try search in internet how to fix it but still got error</p>
  <p>i use Windows 10 for this Oracle19c</p>