Error. Export template excel to NAS in NAV 2013R2

Hi Everyone,

Can you please!

What am I doing wrong?

ExcelBuf.OpenBook_NAS2(FileName); - GOOD


Error in the function ExcelBuf.OpenSheet_NAS2("Template Sheet Name");

OpenSheet_NAS2(SheetName : Text[30])

i := 1;

EndOfLoop := XlWrkBkRTC.Worksheets.Count;
ERROR
A call to System.__ComObject.get_Count failed with this message: The type of one or more arguments does not match the method's parameter type.

WHILE (i <= EndOfLoop) AND (NOT Found) DO BEGIN

XlWrkShtRTC := XlWrkBkRTC.Worksheets.Item(i);
ERROR
A call to System.__ComObject.get_Item failed with this message: The type of one or more arguments does not match the method's parameter type.

IF SheetName = XlWrkShtRTC.Name THEN
Found := TRUE;
i := i + 1;
END;
IF Found THEN
XlWrkShtRTC := XlWrkBkRTC.Worksheets.Item(SheetName)
ELSE
ErrorExcelProcessing(STRSUBSTNO(WorksheetNotFoundErr,SheetName));

Help me, please!!!