OK, so I popped for a new MacBook after my old one broke. And with unquestioning faith in new technology, I innocently ran Migration Assistant after it promised it could load the backup of the old MacBook.
A common problem ensued: I ended up creating a new admin/user without knowing it. Only New Doug is the only one with permission to use New Mac. But only Old Doug has permission to the files from Old Mac that are now on New Mac - i.e., almost everything. So I have a shiny New Mac full of files, apps, etc., that I’m not allowed use.
Note that Old Mac itself wasn’t part of the transfer. The files all came from an external HD backup. Note also that Old Mac runs OSX 10.5, New Mac 10.8.
The typical discussion of the issue is hard for me to understand. It seems to assume that you’ll have TWO users on the new Mac, and that you can just delete the new, sign in as the old, and call him the admin. This is not the case with me - I probably brainfarted during the step where you’re asked to fill in a username and password, and figured I had to enter new ones on a new machine. Makes sense, doesn’t it?
(And yes, I have repaired permissions thru Disk Utility. Didn’t do shit.)
(And no, I’m not about to just stuff everything into the HD/Users/Shared folder and call it a day. That seems like it would cause its own problems.)
The easiest way will be to use the transferred account, as that is the intended outcome of using the Migration Assistant. That is what Kappy is explaining in your last link.
Use your current account with administrator privileges and open System Preferences, go to Users & Groups, click the lock icon and enter your password, then select the account created by the Migration Assistant, and check the checkbox for “Allow user to administer this computer”. You may also want to use the “Change Password…” button to reset the password if you don’t remember your old one.
Now sign into the account transferred from the old Mac and return to the Users & Groups preference pane and delete the originally-created administrator account.
As an Admin, you can do anything.
Just select your other user’s home directory, get info on it, unlock it, and give yourself read and write privileges to it, then click on the gear icon, and apply to enclosed items.
Then, just move those files to your new user’s home directory.
You are best off doing as Cleophus suggests - enabling the imported user as admin and ensuring that you can use the Mac fully with this account and then deleting the first user on the new Mac. This ensures that everything looks the same as on the old Mac. Otherwise many of the old Mac user’s setting won’t work - especially things like the contents the the keychain.