In order to reset/recover your password, you will need to contact your Kerridge KCML administrator. This is the only way to access your hosting account again. Also, you need to know that the application has been discontinued after Automatic Data Processing Inc. acquired Kerridge Computer Co. Ltd.
Note: If you're using a local connection (both Client and Server are installed on the same machine), you can recover your password if you're accessing Kerridge KCML Server clients menu. If you can't recover it, uninstall both Client an Server and install and configure them again.