A Windows 7 needs to be reinstalled on a mechine with an original OEM Windows 7 version. The reason is most often a broken hard-drive with a corrupted partition holding the installation files.
You need to determine the release of your Windows 7 (i.e. Home, Home Premium, Professional, Ultimate, etc.). It is also important to distinguish if your Windows 7 is OEM (distributed with your computer by a manufacturer) or Retail (bought separately in a shop or on-line store).
If your system is still running you can find out your Win7 release by MGADiag from Microsoft.
Here are some codes for releases:
OEM – OEM SLP or OEM System Builder (MGAdiag will distinguish in the License Type field)
007 – VLK MAK
033 – VLK MAK
049 – VLK MAK
050 – Technet Plus Enterprise MAK (do same key used to activate Professional give this CID?)
065 – Technet/MSDN/Bizspark Windows 7 Ultimate
066 – Technet/MSDN/Bizspark Windows 7 Ultimate
067 – Technet/MSDN/Bizspark Windows 7 Ultimate
074 – Retail Windows 7 Ultimate
112 – Retail Windows 7 Home Premium (conflicting info says MSDN)
177 – Retail Windows 7 Professional
220 – Technet/MSDN/Bizspark Windows 7 Professional
230 – Technet/MSDN/Bizspark Windows 7 Home Premium
231 – Technet/MSDN/Bizspark Windows 7 Home Premium
292 – Retail Windows 7 Ultimate?
293 – Retail Windows 7 Ultimate? (maybe Academic)
339 – Retail Windows 7 Home Basic
838 – Technet/MSDN/Bizspark Windows 7 Professional
896 – Retail Windows 7 Home Basic N
929 – Retail Windows 7 Home Basic E
956 – Retail Windows 7 Ultimate (Genuine Advantage store?)
Use an ISO from Microsoft to create bootable device and use it to install Windows on your machine. After the install activate your copy Windows 7 install on-line or by phone.
Steps to be done:
- Download an ISO of the exact Windows 7 release installed on your machine. Alternatives are:ISO from Microsoft [sk-sk] (will need a Product Key), using the Microsoft Windows and Office ISO Download Tool (will let you choose which product to download) or from one of the on-line archives, such as: Official Windows 7 SP1 ISO Image Downloads.
- Use your favorite DVD burning software (on Linux I use K3B) to burn the ISO to a DVD disc or create bootable USB drive in Windows by Windows USB/DVD Download Tool (link2).
- Windows 7 Channel ID portion of Product ID
- How to tell if Windows is Retail or OEM?
- How to reinstall/restore Windows 7 Home Premium OA
- How to: What are my options for obtaining Windows 7 reinstall media?
- Download and re-install Windows 7 Home Premium OA