The following KB article is now available http://support.microsoft.com/kb/929655

This discusses a problem which can typically occur if the MOM Reporting feature is removed and there was a problem contacting the MOM database server during the process.

SYMPTOMS

The MOMX Partitioning and Grooming job runs as expected on a computer that is running Microsoft Operations Manager (MOM) 2005. Additionally, the job does not generate any error messages or error results. However, no data is groomed from the OnePoint database. Therefore, the OnePoint database increases in size.
 

CAUSE

This problem may occur if the following conditions are true:
MOM 2005 Reporting was removed from the computer.
The row that contains the TimeDTSLastRan value was not removed from the ReportingSettings table of the OnePoint database.

Note The TimeDTSLastRan value specifies the date and the time of the last MOM Reporting Data Transformation Services (DTS) job.

RESOLUTION

To resolve this problem, remove the row that contains the TimeDTSLastRan value from the ReportingSettings table of the OnePoint database.

Important Remove this row only if MOM Reporting has been removed from the computer.
 

MORE INFORMATION

When you install MOM Reporting, the MOM 2005 Setup program adds a row that contains the TimeDTSLastRan value to the ReportingSettings table. If you remove MOM Reporting, the MOM 2005 Setup program deletes this row. If this row is blank in the OnePoint database, the MOMXGroomByDays stored procedure determines that MOM Reporting is not installed. Therefore, the MOMXGroomByDays stored procedure grooms the OnePoint database. If this row is present in the OnePoint database, the MOMXGroomByDays stored procedure compares the time that the DTS job last ran to the number of days to retain data setting. From this calculation, the MOMXGroomByDays stored procedure determines whether to groom the OnePoint database. However, because the DTS job no longer runs after you remove MOM Reporting, the TimeDTSLastRan value never changes. Therefore, the MOMXGroomByDays stored procedure does not groom the OnePoint database.

For more information, click the following article number to view the article in the Microsoft Knowledge Base:
899158 (http://support.microsoft.com/kb/899158/) How to troubleshoot DTS and database sizing issues in MOM 2005 Reporting