This article describes an error message that can appear in the Episerver workspace and how to resolve it. The error message is:
Something Went Wrong: Failed loading content with url/url: epi.cms.contentdata:///
This is because there is a site definition issue in the database.
To resolve this issue please look at the tblSiteDefinition in the Episerver CMS database. If there is an incorrect site referenced there then update the value to the correct site.