You can install Helpdesk Support Tool manually, or you can perform an unattended installation.
The Helpdesk Support Tool MSI file has a digital signature, which the Windows Installer infrastructure validates when the installation starts. This includes a certificate revocation check, for which the system needs Internet access. If your Internet connection is slow or unavailable, the installation continues, but only after several timeouts. In such cases, the installer seems to display no progress and does not provide any feedback.