We are not able to activate the publishing Feature. Exception is


"Provisioning did not succeed. Failed to create 'Reusable Content'
Library. Object reference not set to an instance of an object".


Our Page content type was customized. We had added two additional
columns in it. These columns were created by us.


Exception also says lots of problems at SPContentType add, derive
etc.
We removed the columns but in vain. We deactivated the publishing
feature and tried to reactivate it. Now it is not even being
activated
and we receive the above mentioned exceptions.