Binary Rescue

Summer of Mac Love - Week 4 - Software Removal

July 31, 2008 – 6:16 pm

Last week I covered the differences between the software installation processes of OS X and Windows. Over time some of our software outlives its usefulness and has to be removed. This week I will examine the process of removing software from both OS X and Windows.

The Facts

OS X does not have a dedicated software removal program. Software is removed by drag and drop to the trash can.

Windows software is removed through Add/Remove Programs in the Control Panel, which actually launches MSI.EXE (the same application used to install software).

The Windows Installer generates the uninstallation sequence during the original installation providing the ability to rollback versions or completely uninstall software.

Windows maintains a database related to all software installations. This database contains version information regarding DLLs and registry information.

Removing VLC, the most robust video player out there, on a Mac took 13.7 seconds. An attempt to remove VLC on Vista took 87 seconds before it came to an abrupt stop. The VLC application was not recognized by Microsoft Installer and therefore could not be removed. The program was installed and functional, there was no way however to remove it.

The Criteria

• Capability: Does the tool perform the job?
  Software removal mechanisms must perform several functions to be deemed truly capable. The software must be removed from the system while not rendering any of the remaining applications inoperable. The removal must be complete not leaving any trace of the software behind.
• Availability: Is the tool available and working correctly when it is needed?
  The mechanism by which software is removed must be functional when required. How vulnerable to failure is the mechanism itself.
• Usability: Is the user able to intuitively work the tool?
  How easily can the average computer user complete the installation process. Is the process clearly and adequately described? Are any errors experienced clear and useful?
• Efficiency: Does the tool perform the job with as little effort as possible?
  How quickly can the process be completed? How many steps are required? How much interaction with the user is required?

The Results

• Capability: Does the tool perform the job?
  When removing a program in OS X much is left behind. Preference files, application support files, and plugins are all left undisturbed by simply deleting the application. Although a program (AppZapper) exists to perform this function, it is not part of OS X and cannot be considered here. The Windows installer also leaves behind numerous registry keys when a program is uninstalled. Applications in OS X are stand alone executables that are wholly contained. As such their removal cannot affect the programs that remain. The same can not be said of Windows applications. As they share resources in the form of DLLs, fonts and etc, removing a Windows program can and often does leave another program inoperable.
• Availability: Is the tool available and working correctly when it is needed?
  As was the case with Software installation on OS X, the ability always exists as it simply a delete operation on a file. Apparently cut and paste is not prone to problems. This is not true of Windows. There are numerous utilities designed to repair the Windows installer both from Microsoft and third parties. In 6 years I have never had the OS X application removal process fail. As I stated last week, I repair the Windows installer on a weekly basis for my clients.
• Usability: Is the user able to intuitively work the tool?
  Again the results here are a mirror image of last week. The main stumbling block that I have seen in removing OS X applications comes from Windows users who expect the process to be more complicated. Although dragging an unwanted Application to the trash is fairly intuitive, Windows users are accustomed to a series of dialog boxes, confirmation requests and countless progress bars. As was the case with software installation, OS X does suffer from error messages during uninstallation. The most common error results from trying to update an application that is currently running. Closing the application and re-attempting the removal solves the problem almost always.

The Winner

As many of the processes required to remove software are identical to the installation process many of the results from last week are applicable. The first time I chose to remove a program from OS X I was struck by the simplicity. I recall thinking “So all I have to do is put the app in the Trash?! The fact that application removal is this simple makes OS X superior to Windows. The implications of this only reinforce this fact. If by accident you or someone else accidently deletes a program from a Mac you can easily restore the application by dragging it from the trash back to the Applications folder. Windows installation process does not allow for this. Recovering Windows applications requires starting the installation process over from scratch. Additionally when a OS X program is restored from an accidental deletion, all of the users settings are preserved. This is not the case with Windows software. If you really need to delete all traces of an application on OS X you can browse to the Preferences and Application Support folders and delete the files that are named after the relevant program. Try cleaning orphaned items from the registry by hand. Just kidding, please spare yourself the heartache. Messing with the registry is more likely to completely disable Windows than it is to result in anything productive.

Score one more win for OS X:
OS X 4 Windows 0