I have a .NET custom action which installs custom files during install phase.
When I hit "cancel" while the MSI is installing, the log shows this:
MSI (s) (F0:F0) [13:19:56:145]: Executing op: TypeLibraryRegister(...
RegisterTypeLibraries: ...
MSI (s) (F0:F0) [13:19:56:157]: Executing op ...