|To change the username...|
Right click on my computer and select 'manage'
Then click on the + sign next to 'local users and groups'.
Then select the users folder. You'll see the user accounts on your system listed on the right. To rename an account, right click on it and choose rename. I don't think this will mess up any of your settings.
You can also rename your computer by right clicking on my computer then select 'properties'
In the properties menu their is a computer name tab. Select it and click on the change button. There is a field on this screen for the computername. Just change it and click ok. Then it will ask you to reboot.
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