I assume you upgraded not a clean install?
I'm not sure which compatibility issues you would be having. Vista and Windows 7 are like 90% the same thing.
It could be if you upgraded to 64bit, not sure.
If you have the Vista DVD you can always just install it.
I have installed Windows 7 Professional via a download. I previously had Windows Vista Home Premium and much preferred it. I have been having multiple problems with compatibility issues and want to uninstall Windows 7 and got back to Vista. Is that possible? How do I do it?

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