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Posted on May 16, 2013 in PC Maintenance, Troubleshoot Windows | 1 comment

Guide to reinstalling Windows

Thinking of Reinstalling Windows to fix a serious problem or improve PC performance? Read our guide here before you get started. If you’ve tried everything else and just can’t get your computer back into tip-top condition, reinstalling Windows may be the best course of action. There are times when starting from scratch with a clean installation of your operating system is not only sensible but the only viable course of action. If you have been infected with some of the nastier malware, such as the fake antivirus products that are increasingly common, completely reinstalling your operating system is often the only way to be sure of completely removing the threat.

Should I reinstall Windows frequently?

There is no need to reinstall Windows unless you are having a serious problem with the operating system, perhaps caused by malware. There are some individuals who believe Windows should be reinstalled once a year, or even more frequently than that. In fact, one individual once told us he reinstalled Windows XP every month!

Why do some people recommend frequent reinstalls? Simply because it results in a faster computer. However, once you have re-loaded all the software and gadgets you need onto your PC, it may end up performing exactly like it did before you started. Usually, a PC that is well maintained will not inexplicably slow down over its lifespan, so be sure to follow the common troubleshooting and tweaking steps before committing to reinstalling everything.

Reimage, a new, convenient alternative to reinstalling Windows

Since this article was originally written, a fantastic new service has launched called Reimage. Reimage works by connecting to the internet and then checking the system files on your PC against a list of known good versions and then replacing any damaged or corrupted operating system components. The only drawback is that this service comes at a cost. See this article and decide for yourself if Reimage is a viable alternative for you.

Formatting and reinstalling

Formatting hard drives and reinstalling Windows is something we often get asked about here at, so we decided that we would look into the subject in a little more detail. Some users consider reinstalling to be the ultimate cure-all for Windows problems and this is true to an extent. However, there are considerable disadvantages to completely reinstalling your operating system. You will be required to reinstall all your programs, reconfigure all your customizations and settings and of course restore any data from a backup. However, you will be left with a machine that is as clean and responsive as the day you bought it, assuming your problems are software and not hardware related.

Licensing and using the right disc

During reinstallation of Windows, you will need to enter your license key. Usually this string of 25 letters and numbers is on the certificate of authenticity stuck to your PC. If you purchased Windows separately from your computer, your license key will be inside the CD or DVD case.

One issue that frequently trips up users is that of using the correct Windows CD or DVD when reinstalling a computer. Use the wrong disc and you may not be able to enter your license key and complete the installation process. Choosing the correct CD isn’t as simple as just getting the correct version of Windows, as we’ll explain in a moment. If you have the recovery CD that originally came with your computer, or you originally purchased from the store, then you are all set, if not, keep the following pointers in mind before borrowing a friends disc and diving into the reinstallation process.

 Your license key can be found attached to your computer in most cases.

Your license key can be found attached to your computer in most cases.


OEM Vs Retail – OEM stands for Original Equipment Manufacturer. OEM copies of Windows are those pre-installed on PC’s you buy from the shelf. Retail copies of Windows are those which you buy yourself and install on a PC, either one you built yourself or one you are upgrading. OEM installation discs are intended only for the PC that they come bundled with, whereas Retail versions can be uninstalled and then reinstalled on a new computer. You cannot use a Retail copy of Windows when reinstalling an OEM version (or vice-versa), the license key will be rejected.

XP OEM nightmares – To make matters worse, with Windows XP, Microsoft issued different OEM versions of the operating system to different manufacturers. This means that, for example, a DELL OEM installation CD will often not accept the license key when used on a HP or Gateway PC. This situation has apparently improved with Windows Vista and Windows 7, and OEM copies are reported to work on all OEM systems, provided that the versions/editions match.

If you’re unsure if you have the right CD/DVD, we highly recommend taking a full disk backup before beginning the process. If you get part of the way through the installation process and then find you cannot enter your license key, you may be stuck with a non-functional computer.

Microsoft have made this process somewhat less painful in Windows 8 and 10 by allowing users to download a copy of the OS for re-installation using the Media Creation tool. We cover the media creation tool in this tutorial. Theoretically at least, this tool should work with both OEM and retail Windows keys. Of course, you will still need a valid serial number, though on some modern PCs this is now actually embedded into the computers hardware. If you cannot find the serial number on a sticker on your Windows 8 or 10 device, it may simply be embedded onto the hardware and detected automatically by Windows as it reinstalls. You still need to make sure that you download the correct version when using the media creation tool of course, if you’re unsure if you need 32 bit or 64 bit, home or professional then you may need to do a little research first or contact an IT professional.

Repair install (or startup repair) Vs. Full reinstallation

Windows Xp, Vista and 7 users can perform what is known as a repair installation (or confusingly, an upgrade installation in Windows Vista and Windows 7). By using the original Windows CD/DVD, this process attempts to overwrite the current system files with the ones from the disc, thus repairing any files that may have become corrupted without destroying other data on your machine. In practise, this procedure often fails to produce the expected results, but it is certainly worth trying. We cover how to do a repair installation for Windows XP in this tutorial, for Windows Vista in this tutorial and Windows 7 in this tutorial.

Windows Vista and Windows 7 users can also perform a “Startup Repair”. Startup Repair is normally only useful if you cannot start your operating system, it won’t fix other problems like the repair installation (sometimes) does. If you need to perform a startup repair, Vista users should check this video, whille Windows 7 users should check this video.

Repair installations were replaced with the Refresh/Reset feature in Windows 8 and Windows 10. This feature lets you reset/reinstall Windows with just a couple of clicks, provided you can still start your PC of course. We cover the Refresh feature in Windows 8 in this tutorial, and the Reset feature in Windows 10 in this tutorial.

If the above procedures fail, then you may need to perform a full reinstall instead. A full reinstallation will, of course, destroy any data currently on your hard drive, so make sure you have a backup of anything valuable before you begin. If Windows is so badly damaged that you cannot even start your computer, you may need to use a rescue CD from a product such as Acronis True Image. You can then backup all your data to an external hard drive and then access it later when Windows is running smoothly.

Final thoughts

Found the correct media for your computer? Data all backed up? Then you are ready to go. Remember that you will need to reconfigure your computer to boot from CD/DVD discs or a USB device before you can reinstall Windows. See this tutorial for details of how you can access your computers boot menu in order to do this. If you have an older PC that doesn’t have a boot menu, then see this tutorial for details of how to reconfigure your computers BIOS instead.

Certain computer manufacturers have their own special procedures for reinstalling Windows. Dell, for example, often include a special hidden area on the computers hard drive that can be used for reinstalling Windows and resetting the PC to a factory fresh state. If this is the case, you should follow the instructions provided by your computer manufacturer. Hidden recovery areas on a hard drive are no use whatsoever in the event of a hard drive failure however, so make sure you have some kind of operating system recovery media too.

One last thing before you start. Remember that even if you backup your entire hard drive, you will still need to reinstall and reconfigure any programs you wish to use. In almost all cases, this must be done by using the original discs or download files you used when you first installed the software. You cannot normally recover them from your backup. This is because the Windows Registry will be reset. For programs that require extensive configuration, such as e-mail clients like Outlook or Thunderbird, you may wish to search for and use software designed specifically for backing up the program settings.

If you have read and understood all of the above, and you are ready to begin reinstalling Windows, here are our tutorials on completely reinstalling Windows:-

How to perform a complete reinstallation of Windows XP – Part 1
How to perform a complete reinstallation of Windows XP – Part 2

How to perform a complete reinstallation of Windows Vista

How to perform a complete reinstallation of Windows 7

How to perform a complete reinstallation of Windows 8 or 10

Back from reinstalling Windows to Windows Troubleshooting

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1 Comment

  1. I already have a full image backup with windows 7 builtin backup tool but it dont restore my image hang at 50%. Can i use any other software to restore the following image

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