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#11
I'm not sure that I understand what you've tried.
However, the least-effort way to go from Home Premium to Ultimate is through the Anytime Upgrade. The necessary components for the upgrade are already installed with Home Premium; the Anytime Upgrade simply turns them on.
I have never done it, but I have read numerous claims (including one or two in this thread) that you can use an upgrade key to activate the anytime upgrade. I'm not sure that a full version key would do the same, but I'd hope so.
Try using the Ultimate license key in the Anytime Upgrade. If it works at all, you'll have a regular Ultimate version in 10 minutes, and you won't need to use a DVD at all.
I hope that you have some way of backing up all critical files before trying this, though. Doing anything as major as an OS upgarde without having a backup is risky.
If you can't use the key to do an Anytime Upgrade, you could reformat the OS partition and install Win7 from scratch. That would require you to re-install every program, though, and it'd be a lot of work. If you are relying on any pre-installed software, it would be gone.