Hannah can receive emails just fine, but she can't compose them. When she types, she either gets extremely small text or nothing at all. Leo suggests uninstalling Outlook in Control Panel, and reinstalling it. This will reset it to default settings and should resolve her issues. Leo doesn't think it's anything major, just settings that need to be changed.
Even better, she could sign up for a free account at Outlook.com. It's much easier to use and will bypass her issues with Outlook entirely.