Some operations via web interface require a Host credentials.
You can use «oracle owner» user or create additional user, but you should give additional specific system privilege for this user: Log on as a batch job .
How you can it:
1. Go to Start > Control Panel > Administrative Tools > Local Security Policy
2. Open Security Settings > Local Security Policies > User Rights Assignment
3. Double-click on Log on as a batch job from the list of privileges in the right pane.
4. Click on Add User or Group … and enter the name of the OS user whose credentials are being used as the preferred credentials for the host.
5. Click ‘OK’ twice.