OP, are you running Lion or Snow Leopard/earlier?
First, move all the files into the properly renamed user folder (should match the name shown in System Preferences.
For Lion, reboot and hold Cmd-R to boot from the Recovery Partition/Internet Recovery. Once it loads, choose Utilities -> Terminal from the menu bar, then type "resetpassword" without the quotes and hit enter.
For Snow Leopard and earlier versions, insert your OS install disk and reboot while holding C, then when it loads, choose a language and then choose Utilities -> Reset Password from the menu bar.
For both: Choose your drive at the top of the Reset Password utility's window, then the user account which is having trouble from the drop down menu. At the bottom of the window, choose Reset home directory permissions and ACL's.. That step should fix the issue.
jW