Judging by various discussion boards, we have noticed several people are getting ‘Error 1603’ when attempting to install AutoCAD 2012. The error states that the user must ‘install DirectX’ before the installation can commence. To solve this, you need to install DirectX End-User Runtimes (March 2009) from the Microsoft website, and then run the installation again.

Good luck, and enjoy AutoCAD 2012!