Looking to bypass or accept duplicate files

[#1]

I'm currently writing code to pull the files with the same ending into one concatenated file. I'm noticing that when it gets to a duplicate file, the code breaks. Is there a way I could code this to accept the duplicate file as well? I know it may be as simple as renaming the file, but I wanted to reach out for answers first. 

If(
	N Items(lotFiles) == 1, CalibrationTable = lotFiles[1],
	N Items(lotFiles) > 1,
		CalibrationTable = lotFiles[1] << concatenate(lotFiles1, create source column);
		For(i = 1, i <= N Items(lotFiles), i++,
			Close(lotFiles[i], nosave)
		);,
	N Items(lotFiles) == 0,
		Print("no lot data, please try again");
		Return(0);
);

[#2 · Accepted solution]

You have a list of files called 

     lotfiles

and you reference it using a subscript when referring to a single element, and without a subscript when referencing the entire list.  However, you also have a variable referenced as

  lotfiles1

is this an error?

[#3 · Accepted solution]

It looks to me like your second if statement needs work, maybe something like this:

If(
	N Items(lotFiles) == 1, CalibrationTable = lotFiles[1],
	N Items(lotFiles) > 1,
		CalibrationTable = lotFiles[1];
		For(i = 2, i <= N Items(lotFiles), i++,
			 CalibrationTable << concatenate(lotFiles[i], create source column);
			 Close(lotFiles[i], nosave)
		);,
	N Items(lotFiles) == 0,
		Print("no lot data, please try again");
		Return(0);
);