While installing SCCM Client if you get WMI connectivity error messages on the logs follow the mentioned steps.
verify the WMI connectivity from the Server to the client machine
Start->Run->wbemtest.exe
\hostname\root\cimv2
If you still have issues with the WMI connectivity you can resolve the issue by regenerating the WMI Repository.
-On the problematic machine stop the WMI Service
“net stop wmimgmt”
-Rename the existing WMI repository folder
“C:\Windows\System32\wbem\Repository -> Repository.old”
-Start WMI Service
“net start wmimgmt”
After that try to install the SCCM Client.
Thanks !
Shamir