Changed user names and now those accounts have been reset I have 3 accounts set up on my mac. I went into the user folder on the main admin account, the names for the other two accounts in here were different to the ones on the login screen (they were the old names of the accounts before I changed them in System Preferences). I then changed the names to match, now when I log into the other user accounts they have been reset as though they have not been used before. 

As far as I can see the files from those accounts are still in the user folder, they just aren't linking up to the correct account.

How can I fix this?
Go to System Preferences / Users &amp; Groups and create a new user with the Account name or Short Name that you used for the New users. This will correct the ownership of all files in the Home folder, and avoid permissions issues with the contents.

Extracted from Apple's indications for changing user's account name. Steps 5 and 6.