TiWorker is an EXE file (Window Modules Installer Worker (WMIW), as it appears in Task Manager). The Ti prefix stands for Trusted Installer. WMIW is part of Windows Update.
The interesting thing about TiWorker is that it often consumes significant disk (8.9MB/s or 10MB/s) and also has a large memory footprint (e.g. 200-250 MB). Experiences have been noted in the MS Community.
