Resposta curta: as ações que exigem privilégios de administrador acionam o UAC.
A Wikipedia fornece uma lista de tópicos:
Controle de conta de usuário - Tarefas que acionam um prompt do UAC .
- Running an Application as an Administrator
- Changes to system-wide settings or to files in %SystemRoot% or %ProgramFiles%
- Installing and uninstalling applications
- Installing device drivers
- Installing ActiveX controls
- Changing settings for Windows Firewall
- Changing UAC settings
- Configuring Windows Update
- Adding or removing user accounts
- Changing a user’s account type
- Configuring Parental Controls
- Running Task Scheduler
- Restoring backed-up system files
- Viewing or changing another user’s folders and files
- Running Disk Defragmenter