Moved Hard Disk to New Computer, Folders “Access Denied”

Even creating a Windows User of the same name and password as on the old computer, I couldn’t access parts of the drive, for example “My Documents”. The password uses a security id, and the security ID for the user has changed.

http://support.microsoft.com/kb/810881 has the solution:

1. Turn off Simple File Sharing (Security tab, used below, won’t display with this on):
   1. On the Startmenu, click My Computer.
   2. On the Tools menu, click Folder Options, click the View tab.
   3. Under Advanced Settings, click to clear the Use simple file sharing (Recommended) check box, click OK.
2. Right-click the folder that you want to take ownership of, and then click Properties.
3. Click the Security tab. If a Security message appears, click OK.
4. Click Advanced, and then click the Owner tab.
5. In the Name list, click your user name, Administrator if you are logged in as Administrator, or click the Administratorsgroup.Take ownership of the contents of that folder: click to select the Replace owner on subcontainers and objects check box.
6. Click OK. You may receive the following error message, where Folde ris the name of the folder that you want to take ownership of: “You do not have permission to read the contents of directory Folder. Do you want to replace the directory permissions with permissions granting you Full Control? All permissions will be replaced if you press Yes.”
7. Click Yes.

Now you are the owner of that folder.