New clients won't connect to SEPM

I have new test SEP server.  When I create a test install, my clients have trouble connecting to the SEPM.  I installed SEP on test client A and it would not connect.  Then I uninstalled SEP, created a new install package, ran that and it worked. Test client A stays connected.

Next, I tried to install SEP on test client B and I got the same problem.  I've tried numerous installs, and the client just doesn't connect.  In Help -> Troubleshooting, it said the server is offline, which isn't true.  I left the client machine overnight, and now it's connected.  I don't understand is going on.