錯誤：Conf apache2-doc 不存在！安裝 libpng12-0 時

出於某種原因，我在嘗試從 .deb 文件安裝 libpng12-0 時遇到了一個奇怪的錯誤。

命令：

dpkg -i libpng12-0_1.2.50-2+deb8u3_amd64.deb; apt-get install -f

錯誤：

Setting up apache2 (2.4.25-3+deb9u2) ...
info: Executing deferred 'a2enconf apache2-doc' for package apache2-doc
ERROR: Conf apache2-doc does not exist!
dpkg: error processing package apache2 (--configure): subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing: apache2
E: Sub-process /usr/bin/dpkg returned an error code (1)

apache2-doc 已安裝（檢查apt policy apache2-doc：）

我正在嘗試安裝的 .deb 文件：https ://packages.debian.org/jessie/amd64/libpng12-0/download

清除並重新安裝軟體包，可能安裝已損壞。

apt-get purge apache2-doc
apt-get install apache2-doc
dpkg -i libpng12-0_1.2.50-2+deb8u3_amd64.deb; apt-get install -f

引用自：https://unix.stackexchange.com/questions/385233