>>You can keep SQL Server 2008. You need to install SQL Server 2012 separately, don't try any upgrade option, just do a clean installation. Your other SQL Server installations should not interfere.
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>But I don't need it. That's why I was trying to do it all in one shot but I will have to perform a clean uninstall and then a new install.
I don't recommend upgrade. I suggest clean install. As for don't need - do you have 100% control over all environment you're going to install your software? I would not start from uninstalling.
If it's not broken, fix it until it is.
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