I tried many times to get a password for Ubuntu one, but never received a mail (checked Spam and Junk). Does anybody know a solution? Maybe it is a silly question but I did not find a solution.
Have you got an account already? The Ubuntu one Account is not automatically setup..you need to register for it. If No...then you will have set up an account with a password and email address
If yes then enter your email at forgot password
If you still can not retrieve your password then you may be using an unrecognised email address. Have you changed your email address since registration? Set up a new account