Not a valid bookmark.
You tried to set a bookmark to an invalid string.
This error can occur in Visual Basic if you set the Bookmark property to a string that wasn't saved from previously reading a Bookmark property. The following code produces this error:
Dim MyDB As Database, MySet As Dynaset
Dim Placeholder As String
Set MyDB = CurrentDB( )
Set MySet = MyDB.CreateDynaset("Employees")
Placeholder = "1"
MySet.Bookmark = Placeholder ' Not a valid bookmark.