What it sounds like is that your documents were created in a password protected Windows Account. In order to remedy this, we simply need to change ownership. In this instance, simply changing your permissions will not necessarily allow you to perform the required operation.
The quick fix:
From the Windows 7 Desktop, open Windows Explorer (Start Menu > Computer > External HDD) and path to the folder you are attempting to recover. Right click the folder you want and choose the Properties tab. This will bring a pop up menu that will include all of the information about the folder that you have chosen. From here, choose the Security tab at the top of the Properties dialogue box. In the Security tab, you should find a button labeled Advanced towards the bottom. Click this button to bring forth the Advanced Security Settings window. Select the Owner tab from here. The lower half of this menu is titled Change Owner To: and should list all of the user groups on your PC. From here, select theEdit button and this window should change slightly. Select the User Group that you wish to grant ownership too and press Apply. This should effectively change the ownership of the object allowing you to do whatever you need to do.
Hope this helps!
NetLock IT Systems