check for duplicate, orphaned, renamed entries, foldernames containing illegal characters like " or ' etc.

Please report back your results, so we can improve file sync.

I have 2 suspect entries:

For both the FolderPath is an empty string (it is not NULL).

I have a suspicion that these are the default folders for the 'Portals/_default' and 'Portals/0' folders - can you confirm if they should be in the Folders table and what their value should be?

From the error in FCKEditor it seems not to like an empty string:

Message: DotNetNuke.Services.Exceptions.PageLoadException: String cannot be of zero length. Parameter name: oldValue ---> System.ArgumentException: String cannot be of zero length. Parameter name: oldValue at System.String.Replace(String oldValue, String newValue) at DotNetNuke.HtmlEditor.FckHtmlEditorProvider.FCKGalleryBase.Page_Load(Object sender, EventArgs e) at System.EventHandler.Invoke(Object sender, EventArgs e) at System.Web.UI.Control.OnLoad(EventArgs e) at System.Web.UI.Control.LoadRecursive() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---