Effective steps to troubleshoot Yahoo Mail Error Code 475 are
Delete all the emails from Outbox folder
Yahoo sometimes detects as suspicious activity, and it happens multiple times. To eliminate this, Yahoo shows error 475, and tries to remove all the emails.
Change the Yahoo Password of the Email Account
Many individuals report that the Yahoo error code 475 persists when the doubtful activity was identified on your account. This situation mainly persists when the email client unable to send the email. As a result, the error code persists; to get rid of this issue, and try to change the Yahoo password immediately.
Hold until your Yahoo account is unlocked
Yahoo servers take many hours sometimes, so you have to hold down until your yahoo account is unlocked.
Reach yahoo Experts for assistance
By following all the above given steps, if you are not satisfied and still needs to troubleshoot Yahoo mail error code 475. No need to get worry. You can reach the experts for assistance. The experts are available 24/7 for the help.