A corrupt WMI repository can mess up things like the Symantec management agent and its ability to deploy software. If you check properties of "WMI Control" in Computer Management (under Services & Applications), and it shows problems, then the PC likely has a WMI issue. Here's how to repair it.
I use powershell remoting to remotely run this, but it can be done at the PC's command line too. The command format below assumes powershell remoting.
Check the WMI repository.
1. Go to C:\Windows\system32\wbem
2. winmgmt /verifyrepository
If errors are found, try to repair the repository.
1. winmgmt /salvagerepository
Still not working? Then totally rebuild the repository.
1. Stop the Windows Management Instrumentation service.
2. Rename the C:\Windows\system32\wbem\repository folder to something like repository-old
3. Re-register relevant DLLs: cmd.exe /C "for /f %s in ('dir /b *.dll') do regsvr32 /s %s"
4. Re-register all the MOF files: cmd.exe /C "for /f %s in ('dir /b *.mof *.mfl') do mofcomp %s"
5. Start the Windows Management Instrumentation service.