Users GPO are not apply

Hello,

I dont understand something in GPO. i have an old GPO in my server (Windows 2008R2) and this GPO modifiy only "User configuration" but it apply to an OU where there are only computers. This GPO work fine but i dont understand why.

And now i'm trying to deploy printers by GPO for users and my GPO is apply only for computers but not for my users.

Can you help me?

Thank's