It's not an upgrade, not even a downgrade, but a change from 64 bit to 32 bit, regardless that you moving from Windows 7 Home Premium to Windows 7 Ultimate.
But unfortunately it can't be done. Windows 7 will not all itself to be changed from 64 bit to 32 bit, or vice versa.
All you can do is install Windows 7 Ultimate 32 bit as a new Operating System. How you do that depends.
You could try installing it on a new partition on the same hard drive that Win 7 54 bit is installed on, or on a new hard drive, or you can wipe the existing Win 7 64 bit off and start over with the Win 7 32 bit.
I doubt the Windows 7 Ultimate 32 bit will allow you to reformat the hard drive prior to installing, but you can try that. If it doesn't, then use DBAN to wipe the disk, then use the new Win 7 32 bit DVD to format and install. You will lose everything.
Are there no alternatives?
Mark
hey, i have been having problems with my H.P windows 7 home premium 64bits. Some of my programs are not running smoothly, and my friends with 32bit are running the programs fine, so i was thinking of switching to 32bit, but when i try the 35 bit ultimate of windows 7 it giving me an error message, it there any way i can do it and is there any risk.

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