Hello:
I am following database backup/restore approach to upgrade a site from SharePoint 2010 to SharePoint 2013. After performing db restore, it prompted me to upgrade site collection which I initiated. Upgrade process completed with following error. I am not sure how to resolve it. Any pointers?
Feature upgrade action 'CustomUpgradeAction.VideoAndRichMedia' threw an
exception upgrading Feature 'AssetLibrary' in Site 'http://abc.com':
A Web Part or Web Form Control on this Page cannot be displayed or
imported. The type Microsoft.Office.Server.WebControls.DocumentSetPropertiesWebPart, Microsoft.Office.DocumentManagement, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c could not be found or it is not registered as safe.