To recover the no-boot situation, you need to do system restore or revert to Windows 7 RTM:
1. Apply System Restore from the Windows Recovery Environment (WinRE)
At boot-up, Hit F8 --> Repair --> System Recovery Options Window --> System Restore
2. If the system restore failed, you can use the following command to revert to Windows 7 RTM running state:
In the WinRE, run the command prompt and run the following command:
DISM /image:C: /cleanup-image /revertpendingactions
3. You can also perform an inplace upgrade of Windows using your DVD media.