To change your investor password, make sure to log in to the platform, then follow the below steps:
Click on ‘Tools’ in the main toolbar, then select ‘Options’
On the new panel select the ‘Server’ tab
Click the "Change" link
You will be prompted to enter a new password and confirm
Make sure to tick "Change investor (read-only) password
You can also choose to change the Master password in this area
Then click the ‘Ok’ button
Please see the short video below for your reference.