diff --git a/PROMS/VEPROMS User Interface/frmPSI.cs b/PROMS/VEPROMS User Interface/frmPSI.cs
index 62a93598..fb5de576 100644
--- a/PROMS/VEPROMS User Interface/frmPSI.cs	
+++ b/PROMS/VEPROMS User Interface/frmPSI.cs	
@@ -80,7 +80,7 @@ namespace VEPROMS
 					cb.Location = new Point((int)fld.x * 2, (int)fld.y * 2);
 					cb.Visible = true;
 					string val = procConfig.GetValue("PSI", fld.name);
-					cb.Checked = val.ToUpper()[0] == 'Y' ? true : false;
+					cb.Checked = val!=null && val!="" && val.ToUpper()[0] == 'Y' ? true : false;
 					this.Controls.Add(cb);
 				}
 			}