I forget my @me.com password
Can’t recall my @me.com password and my MAC won’t start up
You can reset your Apple ID password from the web here: https://iforgot.apple.com/appleid
If you forget your MobileMe (your.name@me.com) password and you're signed into that account as your Apple ID on another device -- such as your iPhone -- you can reset your Apple ID password on that device. If you forgot your Apple ID password - Apple Support