Windows Vista 32bit & Windows 7 RC 64bit

Hello everyone,
I have downloaded the 64bit version of Windows 7 RC and I am having trouble running the executable within Windows Vista Business Edition 32bit. The pop up error message says: "This version of the file is not compatible with the Windows it is being executed on. According to your computer's system properties determine which version of the software you need x86(32bit) or x64(64bit) then contact the software developer."
Therefore I decided to run the executable before Windows started but when I insert its DVD into my first driver it did not read and proceeded as it was a normal Windows Vista start. After I have decided to change boot device numbers and priorities via BIOS I noticed that one of my optical drivers ,which used to be on the list, was not there. What may have caused this and what is the remedy? By the way I have managed to run the installation disk with the help of the other optical driver. I can access all drivers via Windows interface without any problem.)
Additionally I wonder if I should delete Windows Vista completely prior to installation to avoid any conflicts? Because one is 32bit and the never one is 64bit. Thanks in advance for your contributions.

You will have to do a clean install as you cannot upgrade from 32 to 64 bit. I also would recommend that you install in a dual boot. That way if something goes wrong with W7 (it is still in the testing phase) or something doesn't work for you in 7, you will still have Vista to fall back on.

Gary

Unfortunately I do not have any 32bit edition of Windows Vista so I have to rely on Windows 7 64bit. Is there any way possible to dual boot 64bit and 32bit together?

Sure. See here: Dual Boot Installation with Windows 7 and Vista - Windows 7 Forums. It won't matter that you are installing x64 as you won't be going into Vista for the install. If you have any questions or problems, we'll be around.

Gary