Object reference not set to an instance of an object. c:\wss\EventPlanning.wsp: The Solution installation failed.

You can get the above error when installing any of the Application Server Admin Templates from Microsoft (ITManager, Event Planner, HRManager etc.).

stsadm -o addsolution -filename EventPlanning.wsp

Object reference not set to an instance of an object.
c:\wss\EventPlanning.wsp: The Solution installation failed.

The problem here is that the user you are logged in with does not have the required permissions for the database server. If you run this with the same account as you installed your web applications with, there should be no problem. You will need full control to the content database.

stsadm always uses credentials of the logged in user, unless offcourse you open your command prompt like this “runas /user:mydomain\myuser cmd.exe”.
Exchange mydomain and myuser with the values for the user you want to open a command prompt as.

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