When you use Control Panel to open Add or Remove Programs and then press Add/Remove Windows Components to add an optional Windows component, you receive:
Setup Library wbemupgd.dll could not be loaded, or function OcEntry could not be found. Contact your system administrator. The specific error code is 0x7e.
The application could not be initialized.
This behavior will occur if the WBEM (Web-Based Enterprise Management) folder, %SYSTEMROOT%\SYSTEM32\WBEM, is missing from the PATH environment variable.
You could use Control Panel / System / Advanced / Environment Variables to add it to the end of the PATH variable, under System Variables,
but it is far easier to type regfree -MachineEnvPathADD %SYSTEMROOT%\SYSTEM32\WBEM at a CMD.EXE prompt.