Dear All
It is showing error at this line
Microsoft.Office.Interop.Excel.Workbook aWorkbookObj = appObj.Workbooks.
Open(aPath, 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.
XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
May I know what is wrong here?Please help urgent

public string ReadExcelContents(string aPath, out ArrayList ErrorList, out
string GlobalErrorMessage)
{

string aResTin = string.Empty;
//Initialize local variables
GlobalErrorMessage = "Errors In data in following columns in
excel file ";
ErrorList = new ArrayList();
string aAddress1 = string.Empty;
string aTin = string.Empty;
string aVendor = string.Empty;
string aDBA = string.Empty;
string aAddress2 = string.Empty;
string aCity = string.Empty;
string aState = string.Empty;
string aZip = string.Empty;
string aCountry = string.Empty;
string aTransactionId = string.Empty;
string aTransactionDate = string.Empty;
string aAmount = string.Empty; string aDescription = string.
Empty; string aPgcb = string.Empty;
StringBuilder aStringBuilder = new StringBuilder();

//Create and Initialize the object of excel application
Microsoft.Office.Interop.Excel.ApplicationClass appObj = new
ApplicationClass();

System.Threading.Thread.Sleep(2000);
//Create the workbook by calling open method of excel
Microsoft.Office.Interop.Excel.Workbook aWorkbookObj = appObj.
Workbooks.Open(aPath, 0, true, 5, "", "", true, Microsoft.Office.Interop.
Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);

Microsoft.Office.Interop.Excel.Workbook aWorkbookObj = appObj.
Workbooks.Open(aPath, 0, true, 5, "", "", true, Microsoft.Office.Interop.
Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);

//obtain the active worksheet of excel application
Microsoft.Office.Interop.Excel.Worksheet aWorksheetObj =
(Microsoft.Office.Interop.Excel.Worksheet)aWorkboo kObj.ActiveSheet;

//Get the column count in the excel sheet
//aWorksheetObj.Columns.Count;
int aIndex = 0;
object rowIndex = 2;
object colIndex1 = 1;
object colIndex2 = 2;
object colIndex3 = 3;
object colIndex4 = 4;
object colIndex5 = 5;
object colIndex6 = 6;
object colIndex7 = 7;
object colIndex8 = 8;
object colIndex9 = 9;
object colIndex10 = 10;
object colIndex11 = 11;
object colIndex12 = 12;
object colIndex13 = 13;
object colIndex14 = 14;
object aColIndex = 0;
int aRowCount = aWorksheetObj.UsedRange.Rows.Count;
try
{
while (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex1]).Value2 != null)
{
rowIndex = 2 + aIndex;
if (Convert.ToInt32(rowIndex) aRowCount)
{
break;
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex1]).Value2 == null)
{
}
else
{
aTin = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex1]).Value2.ToString();

}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex2]).Value2 == null)
{

}
else
{
aVendor = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex2]).Value2.ToString();
}

if(((Microsoft.Office.Interop.Excel.Range)aWorkshe etObj.
Cells[rowIndex, colIndex3]).Value2 == null)
{

}
else
{
aDBA = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex3]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex4]).Value2 == null)
{
}
else
{
aAddress1 = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex4]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex5]).Value2 == null)
{
}
else
{
aAddress2 = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex5]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex6]).Value2 == null)
{

}
else
{
aCity = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex6]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex7]).Value2 == null)
{
}
else
{
aState = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex7]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex8]).Value2 == null)
{
}
else
{
aZip = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex8]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex9]).Value2 == null)
{
}
else
{
aCountry = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex9]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex10]).Value2 == null)
{
}
else
{
aTransactionId = ((Microsoft.Office.Interop.Excel.
Range)aWorksheetObj.Cells[rowIndex, colIndex10]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex11]).Value2 == null)
{
}
else
{
aTransactionDate = ((Microsoft.Office.Interop.Excel.
Range)aWorksheetObj.Cells[rowIndex, colIndex11]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex12]).Value2 == null)
{
}
else
{
aAmount = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex12]).Value2.ToString();
}

double aNewAmt = Convert.ToDouble(aAmount);
//string aNewAmount = string.Format("{0:C}", aNewAmt);
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex13]).Value2 == null)
{
}
else
{
aDescription = ((Microsoft.Office.Interop.Excel.
Range)aWorksheetObj.Cells[rowIndex, colIndex13]).Value2.ToString();
}
if (((Microsoft.Office.Interop.Excel.Range)aWorksheet Obj.
Cells[rowIndex, colIndex14]).Value2 == null)
{

}
else
{
aPgcb = ((Microsoft.Office.Interop.Excel.Range)
aWorksheetObj.Cells[rowIndex, colIndex14]).Value2.ToString();
}

Regex aRegTin = new Regex(@"^\d{2}-\d{7}$");
bool aTinFlag = aRegTin.IsMatch(aTin);

Regex aRegexObj = new Regex(@"^\d{3}-?\d{2}-?\d{4}$");
bool aSSNFlag = aRegexObj.IsMatch(aTin);
if((aTinFlag == true) || (aSSNFlag == true))
{
aResTin = RemoveSymbol(aTin);
aStringBuilder.Append(aResTin);
}
else
{

GlobalErrorMessage = GlobalErrorMessage + "Tin" + ",
";
ErrorList.Add(aTin);
}
Regex aRegstate = new Regex(@"^[a-zA-Z]{2}$");
bool aStateFlag = aRegstate.IsMatch(aState);
if (aStateFlag == false)
{

GlobalErrorMessage = GlobalErrorMessage + "State" +
",";
ErrorList.Add(aState);
}
else
{

aStringBuilder.Append(aState);
}
Regex aRegCountry = new Regex(@"^[a-zA-Z]{2}$");
bool aCountryFlag = aRegCountry.IsMatch(aCountry);
if (aCountryFlag == false)
{

GlobalErrorMessage = GlobalErrorMessage + "Country"
+ ",";
ErrorList.Add(aState);
}
else
{
aStringBuilder.Append(aCountry);
}
//Regex aRegTransactionDate = new
Regex(@"^\d{1}[1-9]\/\d{1}[1-9]\/\d{4}$");
Regex aRegTransactionDate = new
Regex(@"(([1-9]|[1-2][0-9]|3[0-1]|0[1-9])[/ /.]([1-9]|1[0-2]|0[1-9])[/ /.
]([1-9][0-9])\d\d)");

bool aTransdateFlag = aRegTransactionDate.
IsMatch(aTransactionDate);
if (aTransdateFlag == false)
{

GlobalErrorMessage = GlobalErrorMessage + " " +
"TransactionDate" + ",";
ErrorList.Add(aTransactionDate);
}
else
{
aStringBuilder.Append(aTransactionDate);
}
bool aAmountFlag = CheckDollarandCommainAmount(aAmount)
;
if (aAmountFlag == true)
{

GlobalErrorMessage = GlobalErrorMessage + "Amount"
+ ",";
ErrorList.Add(aAmount);
}
else
{
//char[] ResultantArr = RemoveDollarandcomma(aAmount)
;
//string aNewAmt = new string(ResultantArr);
//double aNewAmount = Convert.ToDouble(aAmount);
string aNewValue = aNewAmt.ToString("#.##");
aStringBuilder.Append(aNewValue);
}
aStringBuilder.Append(aVendor);
aStringBuilder.Append(aDBA);
aStringBuilder.Append(aAddress1);
aStringBuilder.Append(aAddress2);
aStringBuilder.Append(aCity);
aStringBuilder.Append(aZip);
aStringBuilder.Append(aTransactionId);
aStringBuilder.Append(aDescription);
aStringBuilder.Append(aPgcb);
aIndex++;
}
aWorksheetObj = null;
aWorkbookObj.Close(true, null, null);
appObj.Quit();


}
catch (Exception ex)
{
appObj.Quit();
Console.WriteLine(ex.Message);
}
finally
{
System.Runtime.InteropServices.Marshal.
ReleaseComObject(appObj);
}
return aStringBuilder.ToString();
}

url:http://www.ureader.com/gp/1037-1.aspx