SOLVED Move emails from one domain to another

I had a new domain www.newdomain.com and i want to move all the emails on the user@oldomain.com to user@newdomain.com.

I've tried to do by copying the folders cur, new, tmp from user@oldomain.com to the folder of the user@newdomain.com with the cpanel file manager.

When i see the user on the email section of the cpanel it has the same size of the user in the oldomain, but when i enter to the webmail to see if the emails are on the folders, i see the empty folders, sent, trash, draft.

What i'm doing wrong?

 

Thanks for the reply, it wasnt a permissions problem, the problem was that i've copied only the folders that the file manager show, i forgot to tick the option, show hidden files/folders (dotfile).

And now all is ok!