That "103" in your search? It likely refers to a 103MB installer wrapper, which is just a downloader , not the actual software. The real AutoCAD 2012 requires at least 2GB of space and specific DirectX runtimes.
: Portable versions are often stripped-down or incomplete, lacking critical libraries, online services, and technical support. Key Features of the Original AutoCAD 2012 Autocad 2012 Portable Free Download 103 - Google
If you have a legitimate license for AutoCAD 2012 and want to install it on an older machine, here are the baseline requirements: That "103" in your search
Portable versions frequently crash because they lack the necessary Registry entries and support files required for complex CAD operations. : Portable versions are often stripped-down or incomplete,
: Using pirated software is a violation of copyright laws and can lead to civil or criminal penalties, including heavy fines.