Why only the "adb sideload <filename>" command is working in the adb environment in system recovery? Other commands such as "adb install (package)" plus "adb uninstall (package)" do nothing.
f_canton, knowing why the adb install/uninstall package doesn't function is undoubtedly vital. We will gladly provide you the assistance and information you need. To better assist you, please provide the make and the model of your device. Also, can you please tell us more about what it is that you are trying to do?