Adobe updates are often incremental. You may need to install the 11.0.20 update before applying the 11.0.23 patch.
This specific update was designed to mitigate security vulnerabilities and resolve functional bugs, such as issues with the Reading Order tool and garbled text during email-to-PDF conversions. As the last stable build of Acrobat XI, it represents the most polished version of the "pre-DC" era. download adobe acrobat xi pro 11023 fixed best
: Official downloads have largely been removed from Adobe's primary servers. Some users have had success finding update patches (MSP files) on Adobe’s Enterprise FTP site or through old direct download links. Activation Risks Adobe updates are often incremental