**Hi , Welcome to Microsoft Answers Forum.**Is your windows7 DVD a retail or OEM version? If it is a retail version you can use the Inplace Upgrade installation to reinstall windows7 over itself. You can install windows7 over itself. It is called an In-Place
Upgrade or repair.
I have included instructions on how to complete an In-Place Upgrade.
You can upgrade in-place, which means you can install Windows windoes7and retain your applications, files, and settings as they were in your
previous edition of Windows. An In-Place upgrade is actually a repair installation using the upgrade option. If you have installed Service Pack 1 for Windows windows7
and your original Windows windows7 DVD does not include this Service Pack, then the Upgrade option will be disabled, thus preventing you from doing an in place upgrade. The reason for this is that, by installing Service Pack 1 your system is,
in effect, newer than that of your original Vista DVD.
Therefore, if your original Windows Vista DVD does not contain Service Pack 1 you will need to Uninstall Service Pack 1 from your PC prior
to attempting the upgrade.
Note: After performing In-Place Upgrade, your personal data and installed programs will not be removed but we may need to run Windows Update
to install all the available updates for your system to update these system files to the current version. This troubleshooting process is time consuming and may take several hours to complete.
·
Before you perform an inplace upgrade follow the steps below:
1. Disable or uninstall all security software’s on the computer.
2. Remove all third party CD and DVD burning software.
3. Click on start, in the start search box type appwiz.cpl and press enter. On the left side click on ‘Turn Windows feature On or Off’. Uncheck .Net Framework 3.0, Remote Differential Compression and Windows DFS Replication Service. Click Ok.
- Disable system startup items and third party services
a. Click on Start -> "msconfig" without quotes and hit enter
b. Click on startup tab and then click on disable all
c. Click on services tab and place a check mark on Hide all microsoft services which would be at the bottom left handside of the window and then click on disable all
d. Click on OK and then restart the computer.
4. Start the in-place upgrade.
If you would like to perform the In-place Upgrade, refer to the following steps.
- Start the computer by using the current Operating System.
- Insert the Windows Vista DVD in the computer's DVD drive.
- Use one of the following procedures, as appropriate:
• If Windows
automatically detects the DVD, the Install now screen appears. Click Install now.
• If Windows does not automatically detect the DVD, follow these steps:
a. Click Start,
click Run, type Drive:\setup.exe, and then click OK. Note Drive is the drive letter of the computer's DVD drive.
b. Click Install now.
- When you reach the "Which type of installation do you want?" screen, click Upgrade to upgrade the current operating system to Windows7.
Thanks & Regards,
Hope this helps. Let us know the results.
Vijay – Microsoft Support
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