Microsoft.Net Framework Version 2.0

Windows 7 has the .NET Framework 3.5 and earlier (2.0) redistributables already installed however some application installers are looking for very specific .NET 2.0 files and or registry entires that may not be in the ?Windows 7 versaion of .NET 3.5 (which included .NET 2.0) which can cause error messages:

Example:
TurboTax 2009 can fail to install because it thinks the .NET Framework is not installed, even when it is
http://blogs.msdn.com/astebner/archive/2010/01/26/9953883.aspx

Also you can try the following: How to turn Windows features on or off:
http://windows.microsoft.com/en-US/windows7/Turn-Windows-features-on-or-off

How to check to see if .NET Framework is enabled:
Click Start and in the search enter (without the quotes): "Turn Windows features On or Off".
Next click on the + sign next to the "Microsoft .NET Framework 3.5.1" list of features.
With "Microsoft .NET Framework 3.5.1" expanded place a check mark in both options.
Exit the "Feature" window and reboot your PC.

Turn Windows features on or off
http://windows.microsoft.com/en-US/windows7/Turn-Windows-features-on-or-off

Also:
How to repair the .NET Framework 2.0 and 3.0 on Windows Vista
(The steps in this blog post apply equally to Windows 7 as well)
http://blogs.msdn.com/astebner/archive/2007/03/26/how-to-repair-the-net-framework-2-0-and-3-0-on-windows-vista.aspx

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