Hello Co-members/Dell staff

My son bought a new Dell computer (Inspiron 15R 5520) in US, for me which comes with Windows 8. However, there is no Windows 8 reinstallation disk.

Now, recently during June 2014, I did an experiment with it. The details are given below:

I attached an external HDD containing preinstalled Windows 7 Ultimate 64bit through USB Port. Also made some corrections through BCD software program for dual booting, unknowing that Windows Operating Systems which are installed on USB Flash drive/USB external Hard Drives cannot run as dual boot.

I don't know what happened and the laptop stopped booting flashing a message as follows:

"Status: 0xc0000098 Info: The Windows Boot Configuration Data file does not contain a valid OS entry"

Vexed after making innumerable efforts to restore the system, finally I have installed Windows 8 Pro 64 bit afresh borrowing OS DVD Media (which was supplied with an ACER New PC), from a friend.

But still, I feel to have my Dell system back to work with the original activated Windows 8/8.1 64 bit Operating system.

Is it possible? If yes how? Please provide step by step instructions so that I can follow and implement.

One more thing, may be important, is that while installing Windows 8 Pro, all my original files in a folder name "windows.old". Will it be in any way useful for the retoration of my Dell system.

Thnks in advance.  

Moola SS Sundaram

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