diff --git a/PROMS/VEPROMS User Interface/frmVEPROMS.cs b/PROMS/VEPROMS User Interface/frmVEPROMS.cs
index 5391a093..27b737c7 100644
--- a/PROMS/VEPROMS User Interface/frmVEPROMS.cs	
+++ b/PROMS/VEPROMS User Interface/frmVEPROMS.cs	
@@ -501,7 +501,7 @@ namespace VEPROMS
 			if (pi == null) return;
 			DlgPrintProcedure prnDlg = new DlgPrintProcedure(pi);
 			//added by jcb 20130718 to support create pdf button when multiunit and user selects a unit
-			prnDlg.SelectedSlave = pi.ProcedureConfig.SelectedSlave;
+			prnDlg.SelectedSlave = pi.ProcedureConfig.SelectedSlave == 0 ? -1 : pi.ProcedureConfig.SelectedSlave;
 			//end added by jcb 20130718
 			prnDlg.ShowDialog(this); // RHM 20120925 - Center dialog over PROMS window
 			//added by jcb 20130718 to support create pdf button when multiunit and user selects a unit