How to downgrade Win7 system to reduce Win7 Ultimate to Home Premium Edition Tutorial Introduction

My computer was originally installed genuine Windows 7 Home Premium Edition, but I quickly upgraded to the Ultimate version with the so-called God KEY on the Internet. Recently I found that my system has become a D version. Is there any way to downgrade to the original genuine Windows 7 Home Premium?

[Solutions]

Starting with Vista, Microsoft will package multiple versions in the same installation file (Install.wim). Different versions are installed differently. The license registration is implemented. By default, the version can only be upgraded from low to high (Home Edition & Rarr; Ultimate). The upgrade is implemented by inputting the high version registration code. So after upgrading Windows 7 Home Premium to Ultimate, you can't roll back to the low-level Home Premium, so when you use the genuine recovery disk installation, the system will detect that the current version is higher than the installed version, thus rejecting the installation, as shown below. Show.
The default is not to install the lower version of Windows 7 in the advanced version of the system.

The reason why the upgrade cannot be downgraded is obviously due to the version level, but the installation of Windows 7 actually extracts the Install.wim file to the hard disk. So we can bypass the regular installation and directly downgrade the Home Premium installation files to the Ultimate partition.

[Solution Method]

Because the current system files are in use, file coverage needs to be done in WinPE environment. The PE environment can be accessed using a self-made PE boot disk. You can also press the F8 key after booting, and then select “Repair your computer” to enter WinRE for coverage. In order to facilitate the operation, you can first download “ImageX One-Click Recovery", after downloading, extract it to D:\\Alternative.

Note: ImageX OneKey Recovery is an image-based system-free backup and recovery tool that supports incremental backup. When operating on a system partition, run it under winpe. The software size is about 1.7M, and interested friends can search online “ImageX One-Click Recovery” to download.

Insert the system recovery CD that the computer manufacturer gave, and then copy the "CD\\sources\\install.wim” file to E:\\ for backup, restart the computer to enter the PE environment, and then run the above download to “ ImageX One-Click Recovery & rdquo;, select & ldquo; partition restore & rdquo;, restore the file to E: \\ install.wim, restore the partition to C drive, click & ldquo; execute & rdquo;, as shown below.
Setting Restore Parameters

Small Tips:

Now many brands have no CD-ROM drive, the manufacturer will save the genuine system in the form of recovery image on the local hard disk. For example, ASUS books restore the image name as asus.swm under the hidden partition, such users only need to rename the machine's asus.swm to Install.wim and put it under E:\\.

In the pop-up window, select “Homepremum”image (ie Home Premium Image), and then click “OK” to extract all the Home Premium image expansion to the C drive, as shown below.
Using Home Premium Image Restore System

Restore the image file and restart the computer, so the original system will be downgraded to Home Premium. After entering the system, you need to reactivate the genuine Home Premium. The above method is actually overwriting the installation, so that most of the originally installed software can continue to be used, unlike the computer's own restore, the system will not be restored to the factory state.

Note that there is a certain risk in covering the installation system. Please backup the important data before operation and ask the professional to assist.