You can reinstall Windows 7 using Recovery in Control Panel, under Advanced recovery methods. This method reinstalls Windows 7, either from a recovery image provided by your computer manufacturer, or from your original Windows 7 installation files. You need to reinstall all of the programs that you added, and restore all of your files from a backup.
Back up your files before you begin reinstalling Windows 7 if possible, even if you’re reinstalling Windows 7 on a hard disk partition, and you have personal files on a separate partition. For example, if you have encrypted files, you might not be able to access them after reinstalling Windows. A custom installation replaces the current version of Windows 7 and all personal files.
The advanced methods available in Recovery in Control Panel can return Windows to a usable state if it’s badly damaged. The first method uses a type of backup called a system image, which you need to have created earlier. The second method reinstalls Windows, either from a recovery image provided by your computer manufacturer, or from the original Windows installation files.
You should notice that both methods can result in loss of data. Before beginning either method, you’ll be prompted to back up your personal files to an external location, such as a USB hard disk. After the recovery completes, you can reinstall your programs using the original installation discs or files, and restore your personal files.
When you forgot windows 7 password, and you have access to the admin password, you may try this windows 7 installation to remove windows 7 password. Once you forgot windows 7 admin password, you may only recover your password with a password recovery program. Windows Login Recovery may be the one you can have a try. It can reset windows 7 admin password for you in minutes.