You'll have to install BOINC separately on all those computers, since the installer will make the limited user accounts and correct registry entries that parts of BOINC use. It's not possible to install BOINC on one system, then make a copy of its BOINC and BOINC Data directory and distribute that on other computers due to the accounts and registry entries.

But you can then install BOINC as a service (protected application execution), which runs in the background at all times (even with Windows logged off), while telling through the installer that only the administrator account can control BOINC through BOINC Manager (not checking the option "allow everyone on this computer to control BOINC").

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