By default, installing the Deep Security Agent (DSA) allows you to automatically install the Notifier as well. When you have Notifier installed, its icon will show to all users.
To hide the Notifier icon, follow this article to install the DSA without installing the Notifier on the remote server.
To install the DSA alone, run the following command:
msiexec /i Agent-Core-Windows-9.5.2-2038.x86_64.msi /qb ADDLOCAL=MainApplication
After installing DSA only, be reminded that the Notifier will not be installed in case of upgrading the DSA