NET SEND- Can only send but not receive and send to myself

Ok. My problem is tricky. Net send is enabled, I disabled and reabled it and that didn’t fix the problem. Then I checked the domain. I am on the domain BUT if I try to reset up the domain I am on from the users computer I get the error “access is denied” I went to the server and and the users seems to have the rights it needs to get on the domain. I can send only to myself. I tried using the ip directly same results. I can send, they can’t send to me but I can send to myself. help me please : ) thank you