How to prevent user from installing new hardware

Loading of new drivers would require local admin privileges be assigned to the user.    Just be sure your users are not assigned to the local admin group and you'll be ok.

Some cases can be locked. Buy that kind and you can keep their fingers off the HW. From Windows, of course, do not assign admin (group) IDs to everyone, that defeats the purpose and facilitates worm/virus intrusion that can inherit those same admin (install) rights and really mess things up. For Win9x you are not so secure, but then, they probably cannot succeed with any USB or Wireless anyway.

Could I restrict domain users (even with local admin rights)?  I have encounter an win98 machine that could stop me from installing new hardware.

Sadly, Win98 and 95 do not offer such protections.   Only NT, 2k and XP.     And anyone with local admin rights would be able to install the drivers for new hardware on nt, 2k and XP.     If the user is a member of a domain group that grants local admin access equates to that user having rights to install if they authenticate to the domain.  

Basicaly, local admin rights = install hardware.

Even maybe

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hmm...maybe it is a silly quesiton. ;-) since no body could use software based policy to prevent a guy to physically plug-in some hardware into computer, so what do you guys want? to prevent the hardware's driver install and work? but, even so, some hardware resources (except the space it allocates ;-)) should still be used by the new-installed apapters, cards or drives... which often causes some problems (for either system software or management).

Thanx CrazyOne. I think I would try poledit. One of my user has give me a notebook computer with nothing else installed but cannot install new hardware. I even cannot open the registry editor of that win98 notebook.

When I plug in a new hardware (e.g. nic), a message said that Your system administrator disabled the hardware installion.