Well, isn't that actually what UAC is for? Prevent software to do something, if the user doesn't want it to do.
What is User Account Control?
User Account Control (UAC) is a security component that enables users
to perform common tasks as non-administrators (called standard users
in Windows Vista), and as administrators without having to switch
users, log off, or use Run As. User accounts that are members of the
local Administrators group run most applications as a standard user.
By separating user and administrator functions, UAC helps users move
toward using standard user rights by default.
When an administrator logs on to a computer that is running Windows 7
or Windows Vista, the user is assigned two separate access tokens.
Access tokens, which contain a user's group membership and
authorization and access control data, are used by the Windows
operating system to control what resources and tasks the user can
access. The access control model in earlier Windows operating systems
did not include any failsafe checks to ensure that users truly wanted
to perform a task that required their administrative access token. As
a result, malicious software could install on users' computers without
notifying the users. (This is sometimes referred to as a "silent"
installation.)
So I see two solutions for your problem, depending on the number of computers you need to load with software:
- Tell your people, that there will be a software installation and that they should accept it.
- If there are too many people/PCs to control, then install some kind of software deployment.