This is tougher to notice in an environment that already has Configuration Manager 2012 setup and clients installed (unless you are using OSD on a daily basis), but an environment that is getting a fresh install of Configuration Manager 2012 would notice this quickly since they are pushing out hundreds, if not thousands of clients. As of January 10th you may have noticed that your Configuration Manager client is not installing; unfortunately, that would be the cause of an authentication code error with the MicrosoftPolicyPlatformSetup.msi that you will see in your ccmsetup.log.
“Couldn’t verify ‘C:\Windows\ccmsetup\MicrosoftPolicyPlatformSetup.msi’ authenticode signature. Return code 0x800b0101”
This issue has swept across the TechNet boards and blogs everywhere, but not to fear, there is a fix for this. All that needs to be done is to install the KB 2801987 (http://support.microsoft.com/kb/2801987) on all Primary Site Servers OR use Windows Updates to install the KB 2749655 for Windows XP/7/2003/2008/2008 R2 (http://support.microsoft.com/kb/2749655) and KB 2756872 for Windows 8/2012 (http://support.microsoft.com/kb/2756872) on all the devices before installing the agent. The second option is extra work but it is there just in case the 1st option is not successful.
If you have any questions in regards to this then send me a message on my Twitter (https://twitter.com/JNewtonC). Hope this helps everyone out there and makes life a little easier for you.