AutoCAD install error .net dotnet framework VCREDIST redistributable

http://forums.autodesk.com/t5/installation-licensing/some-products-fail-to-install-result-1603/td-p/3382347
Advanced Solution: In some instances, it is possible to install the product with the existing newer prerequisites already installed. To do this requires more advanced installation knowledge.

Step 1: Copy the entire contents of your installation media to a folder on your local hard drive. If you have a downloaded version, this is not necessary as the files are already on your hard drive.
Step 2: Located the Setup.ini file and create a backup of this file.
Step 3: Open the file in a text editor, such as Notepad.
Step 4: Do a search for the prerequisites that are failing. If your installation is failing on Microsoft Visual C++ Redistributable, do a search for VCREDIST. If it is for Microsoft .NET Framework, search for DOTNET. These items should be located in a PREREQUISITE line that looks similar to this entry:
PREREQUISITE=IE;SSE2;VCREDIST2008SP1X86;VCREDIST2008SP1X64;DIRECTX;DOTNET20;DOTNET4;DOTNET4LANG
Step 5: Delete all instances listed for the prerequisites in the PREREQUISITE= line for that product which is failing. For example, if you were deleting the prerequisite for .NET Framework, your PREREQUISITE= line above would now look like the following:
PREREQUISITE=IE;SSE2;VCREDIST2008SP1X86;VCREDIST2008SP1X64;DIRECTX
Step 6: Delete the section for the #== 3rd Party Components == prerequisite itself between the comment lines. This section will be at the bottom of the Setup.ini file. Again, if you were deleting .NET Framework, you should be left with a blank section similar to this:

#============= DOTNET Begin ===============
#============= DOTNET End ===============

Step 7: Save the Setup.ini file and run the Setup.exe file to begin the Autodesk installation. The installation should now skip the check for the prerequisite files and install without error.

Note: It is important to have the prerequisite programs installed prior to this advanced installation solution. If you do not have the prerequisites properly installed, your Autodesk program will not run!

This process may not work for everyone. Please use caution when modifying your installation files. For an example of an AutoCAD 2012 (vanilla) setup.ini file modified for the removal of .NET Framework, see the attached file. I do not recommend using this file in place of your own.