Under the General tab, towards the bottom you will see classified under Security: This file came from another computer and might be blocked to help protect this computer. Click on Unblock.

Windows Security monitors files added to your PC, especially those from the internet. If a file seems harmful, you'll see a warning "These files might be harmful to your computer".

Here's the situation: Windows XP, Service Pack 2 with latest hotfixes. Certain files, in this case printer drivers, are listed under their attributes as being blocked. The exact message on the ...