are doing an database attach upgrade and the upgrade failed while performing the Mount-SPContentDatabase and got the errors "Feature upgrade failed for Feature " and "Exception: Object reference not set to an instance of an object".
Did a deploy of an upgraded version of the solution that were missing and tried to continue the upgrade by executing upgrade-spcontentdatabase but i still got the problem. All other site collections were upgraded and now only 1 site collection "Needs upgrade" (checked with the command "Stsadm -o localupgradestatus" )
Can the sites in the site collection that "Needs Upgrade" still be used? Can i ignore these sites and put the server into production?
I can't find out from microsoft what it means that a site collection has not been upgraded? Does anybody else no that?