Thank you. I had set up SCCM 2012 SP1 about 2 weeks ago. Deployment to 15 clients went fine. In the last week I tried to add to 2 more clients and could not get to install. Nothings worked (SUP, push and manual install from client). Never would have thought an expired Cert problem.
Even though the CU instructions said to install prior to SCCM SP1 installation, no problems when CU applied to existing install. Client deployment now works fine.
You might want to PIN this for a while until MS releases an automatic update.