After installing a clean SharePoint 2010 server, we encountered a Timer Job error in our event logs:
Event ID: 6398
The Execute method of job definition Microsoft.SharePoint.Administration.SPSqmTimerJobDefinition (ID 7f72abfd-0175-4764-b4fd-04ec04b3853f) threw an exception. More information is included below.
Data is Null. This method or property cannot be called on Null values.
As the error states this is an Timer Job definition problem or error, we reviewed the job history:
- Open the Central Admin
- Select Monitoring from the left menu
- Select Review job definitions from the left menu
- Select Job history from the left menu
- Select Failed jobs from the View pull down on the right top side
You are now presented with all failed Timer jobs. In our case we opened the CEIP Data Collection job by clicking on failed. It showed us the same error.
The CEIP Data Collection job is a Customer Experience Improvement Program job and is known to cause this error, as explained in http://support.microsoft.com/kb/2616940 
You can safely disable the job and the error will go away.
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