Object reference not set, ERROR when adding a new webpart

Question

I wanted to try tag cloud in a SharePoint server I maintain, I grabbed Nuage from www.codeplex.com and when I try to install , I get the below error

C:>stsadm -o addsolution -filename TagCloud.Sharepoint.Solution.wsp

Object reference not set to an instance of an object. TagCloud.Sharepoint.Solution.wsp: The Solution installation failed

Answer 1

Did you tried Installing it as Farm Admin sometime you get this error when you are running it as non farm Admin. Also make sure the Timer Job is running

Answer 2

To determine if this is a permission issues, try this stsadm command to enumerate your sites:

stsadm -o enumsites -url http://<YOUR URL>

If you get a login failed message, then you will need to run your stsadm command with a user account that has necessary permissions. The farm account is a good bet.