My Toshiba Satellite L300 caught a virus and refused to boot. It would only cycle into repair mode and would not even boot into Safe Mode. After three days I decided to complete a system restore, but while it was restoring there was some kind of power surge that stopped the computer. Now whenever the computer starts a message appears saying that there is a corrupt or missing file and it will not proceed past that point. There were no recovery CDs provided with the computer so I cannot figure out how to reinstall Windows. Can you assist?

It seems that you had quite a series of bad events occur which have resulted in your computer now becoming completely unbootable! You are correct that in this situation your best option is to reinstall Windows from scratch. However, before doing so you should realise that this will result in all data on your computer being lost, since the reinstallation process is destructive. If you have an up-to-date backup of your data then this should not be a problem, since you can restore the data from backup once your computer has been recovered. However, if you do not have a backup then we should resist rushing into this process of reinstalling Windows.

At this point (unless there is something physically/mechanically wrong with the hard drive) all your data should still be intact on the drive (barring the virus having done anything to your data, such as going on a deletion spree) just that the operating system has been corrupted and cannot be booted. As such, your data may well be intact but you have no way of accessing that data at the moment. However, if the drive can be removed from the computer and connected to another (working) computer it could be possible for the data to be read and then copied off the drive. This may seem like a complicated process, but for a computer technician is a fairly straight-forward and they have the required tools to complete this task. Therefore, if you do need your data recovered I suggest taking the computer to a technician and asking them to recover the data from the drive and copy it across to an external hard drive (or like). Be aware, if your computer is still under warranty then this could void the warranty since the technician may need to take the laptop apart to access and remove the hard drive. Should this be the case I suggest you first contact Toshiba and explain the situation since they could likely recommend an authorised repairer who could perhaps complete the data recovery task without voiding the warranty on your computer.

If you have a recent backup of your data then we can go straight into reinstalling Windows. You mentioned that the computer did not come with any recovery or reinstallation CDs. This is normal for more recent computers, as some computer manufacturers do not provide physical recovery and reinstallation CDs but instead have a hidden recovery partition on the hard drive. This is a hidden portion of the hard drive that contains all of the reinstallation files. From the computer manufacturers perspective this is likely to be less expensive than having to produce recovery CDs and from the user perspective can be more convenient as you don’t have to store (and potentially lose) the recovery CDs that come with the computer. In the documentation (manual) that came with your computer there should be a section which deals with reinstalling the operating system on the computer. This should instruct you to press a certain key or key combination while the computer is starting-up (e.g. has all of the Toshiba logo, etc. displaying immediately after power-on) which will tell the computer to enter recovery mode and allow for the reinstallation of Windows. Once you have entered this mode follow the prompts (or instructions in the computer manual) to commence the reinstallation process.

However, one somewhat fatal flaw with including the recovery data on a hidden hard drive partition is the situation that arises should the hard drive itself be faulty. You will learn this fairly quickly because when you attempt to enter the recovery mode an error message would appear, or recovery mode would just refuse to start. In this situation you would more than likely need to contact the computer manufacturer anyway for a replacement hard drive and either they would send the hard drive with a recovery partition included, or alternatively send the drive with a set of recovery CDs.

In any case, through following the instructions above you should be able to restore your computer to a working state, hopefully with all of your personal data intact. If you have not already then as a result of this experience you should seriously consider implementing a backup regime on your computer. There are many potential ways that data on your computer could get corrupted or inaccessible, through virus infections (as you have discovered) along with operating system corruption for unknown reasons through to mechanical failure of the computer hard drive. Therefore, having a scheduled automatic backup to an external drive is a very important aspect that should be seriously considered.