diff --git a/PROMS/VEPROMS User Interface/DlgPrintProcedure.cs b/PROMS/VEPROMS User Interface/DlgPrintProcedure.cs
index 53180a8f..6b4b1c81 100644
--- a/PROMS/VEPROMS User Interface/DlgPrintProcedure.cs	
+++ b/PROMS/VEPROMS User Interface/DlgPrintProcedure.cs	
@@ -1134,7 +1134,8 @@ namespace VEPROMS
 			{
 				if (_MergedPfd.MergedPdfs != null && _MergedPfd.MergedPdfs.Count > 0)
 				{
-						System.Diagnostics.Process sdp = System.Diagnostics.Process.Start(_MergedPfd.MergedFileName);
+					System.Diagnostics.Process sdp = System.Diagnostics.Process.Start(_MergedPfd.MergedFileName);
+					if (sdp != null) // B2020-055 if the current .NET version does not recognize the program used to display the PDF, it will return a NULL (ex. Microsoft Edge)
 						sdp.WaitForInputIdle();
 				}
 			}