Unfortunately, Hotmail’s own SMTP puts a limit on outcoming emails, to deter spammers from taking advantage of it, and make their shared IPs work better without email queues: so you can send a maximum of 300 messages per day and manage up to 100 recipients per message.
To do that, it’s necessary to set up Hotmail’s SMTP settings. In fact, a mail client can be handier and generally provides more tools for your account management. Webmail services like Hotmail are great to check your email account online: but you might want to access your inbox from a desktop software like Mozilla Thunderbird or Microsoft Outlook.
