If you are encountering errors related to netfx20sp1 or are trying to run legacy software that demands it, do attempt to install the old 2.0 SP1 package.
: It is a critical prerequisite for systems moving toward .NET Framework 3.0 SP1 and .NET Framework 3.5. netfx20sp1 upd
: Manually renaming the corrupt assembly folders in C:\WINDOWS\Microsoft.NET\Framework can force the installer to recreate a healthy directory. If you are encountering errors related to netfx20sp1