I have opmanager plus the netflow plugin installed. I have a problem when tried to upgrade Netflow Plugin into new version. when I used updatemanager.bat, found error message : "Could not find the main class: com.adventnet.tools.update.installer.UpdateManager.  Program will exit."
Detail version :
1. Opmanager version 11500
2. Netflow Plugin version 9861

How do I fix this problem. Can anyone help me.

regards,