I have a large list that I'm having a heck of a time moving from one sharepoint cluster to another. The error I'm getting is when I load the content into the list (via cut and paste), I get an error stating "The user does not exist or is not unique".
This error occurs even when I click the little "open book icon" to look up the user. Everything populates normally, but the error will not resolve. If I go in and manually create a item in this list, then everything works properly.
I even tried to create a list item manually and then copy that item's contents to the next row. However that errorred out exact same way? What in the world is wrong here? I'm using the Gantt Chart - Project Task List on SharePoint 2010 Enterprise.