There are two settings that control emails that are sent to clients disable_client_access and send_client_emails
The first setting to check is disable_client_access. If this value is set to false, the application will always send the client welcome emails with their username and password, regardless of the value in send_client_emails. If disable_client_access is set to true, the application will not send any emails to clients regardless of the value in send_client_emails.
The second parameter that can affect which emails that are sent to clients is send_client_emails. This parameter is only relevant if you have disable_client_access set to false. There may be instances where you want to allow the client to log in, but you do not want the client to receive any status emails from the application. Setting this parameter to false, will disable all status emails from the app, but it will not disable the welcome email. To disable the welcome email AND all status emails, you must set disable_client_access to true.