I don't think you can transfer the OS to your new PC by just copying. It's necessary to reinstall.
If you had a retail version, you can download a replacement install disk from http://www.microsoft.com/en-us/software-recovery. It should accept the original license key (use Belarc Advisor if you can't find the the original that came with the disk).
If that won't work, you'll need to buy another OS, be it Windows 7 or 8, or install Linux.
Kees
Hello!
I ordered parts online the other night to make a new desktop. Problem is I cannot find my windows 7 disk and I did not nor do I want to spend the money to buy a new one. I'm assuming my best option would be to transfer my information from my HDD to my new SSD. I just don't know how to do this properly. There are plenty of videos online that show how to plug up the SSD, download some program and copy to a new SSD. My main issue is as follows, and none of these videos cover this issue that I know of.
My old system ran on a AMD Phenom II, with a Gigabyte MOBO, and a Raedon HD 6700.
My new system is going to be a i5, with an ASUS MOBO, and an EVGA Nvidia gpu.
First of all, is it even possible to keep the bulk of my current HDD information and transfer it to the SSD, plug it up make a new adjustments or whatever and it works fine?
Should I invest in a new copy of windows and start from scratch because the task before me is is fu***** monumental???!?!?!
Should I pay some dude at a sketchy computer store down the street to do this for me for under $50 bucks if he will accept that as pay?? Because I wouldn't pay more than that because then I could buy the new windows 8.
Obviously I don't know what to do. I should be getting all the parts in today, I'll assemble the new machine tonight, hopefully I'll have some answers on here later today so that I can know what steps to take as far as getting my new system up and running.
Thank you all for your time and any suggestions, seriously any suggestions...

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