try this:
In order to collect WMI data from the remote machine, the user connecting must have rights on the remote machine. I'm confident that you will need to install splunk as a specific user and then give that user WMI rights on the collection target. In addition, 6.0.x and prior, your specific user will also have to be a member of the local admin group on the machine splunk is installed on.
Or check these out:
http://docs.splunk.com/Documentation/Splunk/6.4.3/Data/MonitorWMIdata
http://docs.splunk.com/Documentation/Splunk/latest/Installation/InstallonWindows#Choose_the_user_Splunk_should_run_as
http://docs.splunk.com/Documentation/Splunk/latest/Data/ConsiderationsfordecidinghowtomonitorWindowsdata
... View more