in my experience to date, .NET FW 4.0 is quite isolated from .NET FW 3.5.1 (on Windows7 and WS2008R2), and doesn't affect base Windows features/functions in a negative way.
It's kind of impossible for us to know if you have something configured or installed in your environment which might be affected by installing .NET FW 4.0, but if you do have IIS/web services or applications running on these machines, it's possible
these might be affected, so you should take care, do backups, or clone off to a test machine, etc.
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Edited byDonPickSunday, July 21, 2013 11:02 AMfix typo
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