Yuri,
Still I think that string is a typo (I can use a single quote as Note,no?). However there is a problem with .Source. This works:

        Dim ExcelFile As String
        Dim cnnExcel As ADODB.Connection
        Dim rstExcel As ADODB.Recordset

        ExcelFile = "c:\temp\customer.xls"
        cnnExcel = CreateObject("adodb.Connection")
        cnnExcel.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + _
          Excelfile + ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1';")

        ' Open recordsets
        rstExcel = New ADODB.Recordset

        rstExcel.ActiveConnection = cnnExcel
        rstExcel.CursorLocation = ADODB.CursorLocationEnum.adUseClient
        rstExcel.CursorType = ADODB.CursorTypeEnum.adOpenStatic
        rstExcel.LockType = ADODB.LockTypeEnum.adLockReadOnly
        rstExcel.Open("select * from [customer$]")

        'rstExcel.Open(strSelect, cnnExcel, ADODB.CursorTypeEnum.adOpenStatic, ADODB.LockTypeEnum.adLockReadOnly, -1)

>Cetin,
>
>"+" may be used here in VB, though "&" is recommended. Anyway, for both syntaxes there are no errors when open connection, but still the error when open the recordset.
>
>
>
>>Yuri,
>>I'm really confused about what's not working.
>>I don't know VB but wouldn't it be a & instead of + for concatenation? Quotes do match - sounds like there is an extra one before ExcelFile.
>>Cetin
>>
>>>Cetin,
>>>
>>>The problem is not with the Adapter, it works. I would prefer to follow the existing working code in VB/VFP where ADO recordset is used. If it works there, then why it does not work in VB.NET?
>>>
>>>cnnExcel = CreateObject("adodb.Connection")
>>>cnnExcel.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + _
>>> ' Excelfile + ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1';")
>>>
>>>....
>>>' Open recordsets
>>>Dim rstExcel As ADODB.Recordset
>>>rstExcel = New ADODB.Recordset
>>> With rstExcel
>>> .ActiveConnection = cnnExcel
>>> .CursorLocation = ADODB.CursorLocationEnum.adUseClient
>>> .CursorType = ADODB.CursorTypeEnum.adOpenStatic
>>> .LockType = ADODB.LockTypeEnum.adLockReadOnly
>>>
>>>* the line below gives an error
>>> .Source = "SELECT * from [Matched$]"
>>>....
>>>
>>>
>>>
>>>The error is:
>>>VB Error # 3001 was generated by ADODB.Recordset
>>>Arguments are of the wrong type, are out of acceptable range, or are in conflict with one another.
>>>
>>>Cannot figure out why it works in VB and VFP, but does not work in VB NET, and what kind of arguments are not accepted.
>>>
>>>Any ideas of where to look into?
>>>
>>>
>>>>
>>>>Yuri,
>>>>Both versions are working for me:
>>>>

>>>>			string strSQL = "select * from [customer$]";
>>>>			string strCon = @"Provider=Microsoft.Jet.OLEDB.4.0;
>>>>  Data Source=c:\temp\customer.xls;
>>>>  Extended Properties='Excel 8.0;HDR=Yes;IMEX=1'";
>>>>
>>>>//			OleDbConnection con = new OleDbConnection(strCon);
>>>>//			OleDbDataAdapter da = new OleDbDataAdapter(strSQL, con);
>>>>
>>>>			OleDbDataAdapter da = new OleDbDataAdapter(strSQL, strCon);
>>>>			DataSet ds = new DataSet();
>>>>			da.Fill(ds);
>>>>			foreach(DataRow dr in ds.Tables[0].Rows)
>>>>			{
>>>>				Console.WriteLine( "{0} {1}",dr["cust_id"], dr["contact"] );
>>>>			}
>>>>
>>>>

Cetin