3 ways to repair Windows 7 installs without reformatting your hard drive

Over time, your Windows PC may become corrupt, either due to a system crash, ¬†installed and uninstalled programs not uninstalling properly, or through viruses/trojans, malware etc, but for whatever reason do not just simply ‘wipe’ your drive clean and start again, especially if you have important personal data on your PC that is not re-creatable. If the corruption was due to a virus please see my article on Virus removal before commencing a repair, if the virus is still present, there is no point in trying to do a repair install.

Warning: Please Backup any data first if you possible can, either to USB sticks, external hard drives or CD/DVD discs.

In this article, I will explain how to try to recover your Windows install without wiping your hard drive. The first thing to do in the case of a corrupted Windows system is DON’T PANIC! This can cause irrational decisions which you may regret later. However, if you’re in the situation of having a corrupted Windows installation, there are several methods of recovery available.

Ideally, for this article, you will need a Windows 7 disc. Unfortunately, these days, most PC’s don’t come shipped with Windows discs, as they used to, I personally think that there should be a legal requirement to include discs for supplied software, but I digress. If you don’t have a Windows disc you can download an ISO disc image of one from digitalriver.com and burn the ISO image to a DVD.

Windows 7 Home Premium 32Bit: http://msft.digitalrivercontent.net/win/X17-58996.iso
Windows 7 Home Premium 64Bit: http://msft.digitalrivercontent.net/win/X17-58997.iso

Windows 7 Professional 32Bit: http://msft.digitalrivercontent.net/win/X17-59183.iso
Windows 7 Professional 64Bit: http://msft.digitalrivercontent.net/win/X17-59186.iso

Windows 7 Ultimate 32Bit: http://msft.digitalrivercontent.net/win/X17-59463.iso
Windows 7 Ultimate 64Bit: http://msft.digitalrivercontent.net/win/X17-59465.iso

Your serial number should be on a COA (Certificate Of Authenticity) sticker somewhere on your computer case just in case you need to re-activate Windows, but unless you’ve changed any hardware in your system, like upgrading the RAM, Motherboard or Processor or Graphics card, then this is unlikely.

Method 1 – Windows System Restore.

Windows System Restore was a usefull feature introduced in Windows XP, to deal with these kind of sitautions where Windows installation maybe damaged. Hopefully, you have Windows System Restore turned on and have some restore points created. The best advice would be to pick a restore point on the date when you knew the PC last worked correctly.

Method 2 – Repair re-install

Once you have burned your appropriate Windows version to disc, the next thing to do is to insert the disc into the drive, them restart the computer and boot it from the CD-DVD drive. There may or may not an option to boot from the drive with a one-time boot menu, as is the case on DELL computers. This menu can be accessed from the F12 key immediately you see the DELL logo after booting. If you have a different PC, check your instructions on how to boot from the DVD-RW drive. If you built the PC yourself, or it’s a custom build, then you will have to enter the BIOS and alter the drive boot order so that it boots from the DVD drive. There maybe a boot menu option depending on your motherboard. Once you have your PC booting from the Windows install DVD, there are a few possibilities to try.

It is sometimes possible, but not always possible to recover your Windows install from a repair install. This is available from the pre-boot environment section of the install CD.
When you have booted from the DVD, there will be some options, either ‘Install Now’ or ‘Repair’


Then the repairer will search for Windows installation, when it’s found one, it will attempt repairs, this may take a while and please do not turn off your computer during this process otherwise your Windows installation maybe permanently damaged to the point that you have to reforat and reinstall.

Method 3 – Upgrade install

There is a third way if the other two didn’t work.

An upgrade install will install Windows over the current installation, to repair any missing or corrupted files.


Once the upgrade option has been selected, then Windows will re-install itself in the usual way, and should repair/replace your damaged system files.


Hopefully, if you’ve followed the advice above, you should have a fully working system again.

About admin

Mike Gisbourne is an IT Professional/System builder from the UK with 20 years experience of PC building. Building PC's since 8086 days and Windows 3.1/95. Mike specialises in PC hardware, server administration, hosting. He is also a musician, keyboard player.