When InstallShield was founded in 1987 all companies were making their own installers. https://en.m.wikipedia.org/wiki/InstallShield https://en.m.wikipedia.org

When InstallShield was founded in 1987 all companies were making their own installers. https://en.m.wikipedia.org/wiki/InstallShield https://en.m.wikipedia.org/wiki/InstallShield MSFT released MSI 1.0 in 1999. https://en.m.wikipedia.org/wiki/Windows_Installer https://en.m.wikipedia.org/wiki/Windows_Installer Post 2008 or so, there was a very good question of why anyone would use anything other than *.msi on windows. But most Installshield users by then were building those packages with InstallShield by then. These days, lightweight apps and dev tools are still preferred to use *.msi or *.exe based formats instead of windows store apps. Partly because it is quick and dirty to do so, and cheap using things like WIX and NSIS. But InstallShield still has a legacy base among less sophisticated users; it is easier than WIX and more robust than NSIS and the like. Windows Store package formats are superior in most ways.