Can't install .Net framework 4.0

Question

I downloaded .Net framework 4.0 "dotNetFx40_Full_x86_x64_SC.exe" on windows server 2008 R2, 64 bit OS and every time i run the exe file i got an error message "an error was encountered unspecified error"

first it run and give me the below:

then this error

Answer 1

I figured it out, do the following:

1. in Control Panel --> internet options --> privacy --> settings --> blocking level: make it Low
2. go to this link: http://www.microsoft.com/download/en/confirmation.aspx?id=17851 and install the web installer edition of the .net framework 4.0, there is something with the windows installer that permits the stand alone version to be installed on windows server 2008 R2