Please try the below general troubleshooting steps :
> Enable the hidden Admin Account on Windows 7 ( Ref : http://www.howtogeek.com/howto/windows-vista/enable-the-hidden-adminis trator-account-on-windows-vista/ )
> Disable all Non-Microsoft Startup Services. (Ref : http://helpx.adobe.com/x-productkb/global/disable-startup-items-servic es-windows.html )
> Disable all the Antivirus softwares like CA, Norton,Mc Afee etc. temporarily from the computer.
Reboot and Install and check.
