The type 'Wondersoft.Bill.Transaction.WebForm1' is ambiguous: it could come from assembly 'E:\Wondersoft\ibcUAT\Application\shopaid\bin\Wondersoft.Bill.Transaction.ZeitXtraRetail2.DLL' or from assembly 'E:\Wondersoft\ibcUAT\Application\shopaid\bin\Wondersoft.Bill.Transaction.CraftLandXtra4Bill.DLL'. Please specify the assembly explicitly in the type name.