Because 11.0.23 is no longer patched, using it on modern operating systems may expose systems to security vulnerabilities.
Version 11.0.23 provides a fascinating look into the security landscape of its time. While it was the most secure version of the XI family, it remains a product that, today, is essentially a historical artifact. adobe reader xi version 11.0.23
One of the primary reasons users cling to Reader XI 11.0.23 is its ability to run on older hardware and legacy operating systems. Because 11