Apache is not listed amongst the installed components in Plesk Panel → Settings → Server Components. However, Apache is actually installed and working. As a result, there is no possibility to control Apache via Plesk Panel GUI.
RESOLUTIONReplace package mng with the one attached,in accordance with your OS architecture.
Debian 5 x86
Debian 5 x64
This problem has been fixed in Parallels Panel 10.4.