Problems "upgrading"

I am using a proper Windows 7 Ultimate disc to reload windows via the upgrade option. This is something I have done in the past without problems. I have tried for the last 2 days and after 5 hours and at the point of booting up into windows gives me the message that the upgrade has been unsuccessful and is reloading the previous version. Can anyone tell me why. The original version on my laptop is a legit copy as is the disc I have which is also the disc the copy on my laptop was originally installed from. This is driving me nuts as well as wasting an awful lot of time.

Whilst I would agree normally, I have used this upgrade process in the past a couple of time with complete success. The Windows 7 disc is the full version not an upgrade disc. This time I was not even asked for the product key which I was previously. My laptop is in constant use so a fresh install at the moment is completely out of the question hence the question.

I am wondering why you want to reinstall Windows 7? And, why have you have done it a couple times in the past? Why not try one of your system recovery options, rather than reinstalling? What are the system recovery options in Windows 7?

Cassandra
Microsoft Windows Outreach

This seems a more peculiar way of reinstalling. Perhaps you do a lot of software testing or hardware testing?

IMO, the best way to do what you are trying to is to image your system at regular installs, using a program like Macrium Reflect. Restoring from that image will revert you to exactly the system you imaged plus no reactivation is required. Theres a tutorial on this, check the Tutorials section.

The system restore doesn't want to restore even though it has restore points showing so I wanted to run a repair of windows which as for as I can see is done by running the upgrade option as it's the only other one to the clean install. I have Windows 7 already installed and have used the upgrade option to repair it in the past. It doesn't seem to want to know this time. Yes I would have used a backup but my NAS drive packed up 3 weeks ago and I haven't got round to replacing it yet.

Check your HD.
SFC /SCANNOW Command - System File Checker
Disk Check

Check with a hard drive diagnostic tools.
Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp.

Then you should say you are doing a Repair Install