Upgrade 2005 Express to 2008 R2 Express -Instance changed to INACTIVE

Hi,
We have an requiremt to convert SQL 2005 to SQL 2008 R2.
Our product will have own instance to host (XXXXX).
So the requirement is to update 2005 XXXXX to 2008 XXXXX.
But the installation goes wrong in the middle and the upgraded instance changed to INACTIVE.
We found that INACTIVE by REGISTRY surfing.
Note: we have used normal Package.xml to upgrade.
The issue occurs only in one syetem.
Since we need to deliver the DVD to customers, we dont want them to face the issue.
Please do the needful.
Thanks
Muthukumar S

My Error List:
Overall summary:   Final result:                  SQL Server upgrade failed. To continue, investigate the
reason for the failure, correct ...