GPO for OU, work for 1-2 not 3

Hello. I have configured AD and made a new OU named "Schulung" in it.

I put 3 users (pc1 pc2 pc3) in it with server based profiles (\\server\pc1 pc2 etc..)

I made a new GP for my OU "Shulung". I disabled a few icons on the desktop. But only user (pc1 pc2) are subjected to the new GP. User pc3 is not affeted by it. Why?

Thanks

Is the policy on a per-user or per-computer basis?

Thanks for trying to help. But i already solved it :-)