If you are not able to send and receive emails from Hotmail account you have to ensure that you follow the terms of use laid by Hotmail. Do not send too many mails from your account within a short period of time. Do not you use your Hotmail account for forwarding chain mails, or a single mail to multiple users at one go. All these activities are considered as spam by yahoo. To get more idea about creating strong password you have to speak to Hotmail customer support team and learn from them about the things you’ve to keep in mind while using your Hotmail account. check out :- http://www.mailcustomersupport.com/hotmail-technical-support