In the search box - type Windows Mail (probably windows live mail) and you should then find it. Assume that it is still your default email client.
When you state "vanished", vanished from where? Where do you normally click to open it?
OnePlus 5 review
Alice Saey's mesmerising animation for Dutch singer Mark Lotterman
iPad Pro 10.5in (2017) review
Comment booster votre iPhone ?