If ActiveSheet.QueryTables.Count > 0 Then
    With ActiveSheet.QueryTables(1)
    .Sql = sqlstring
    .Refresh
    End With
Else
    connstring = _
    "ODBC;DSN=XXX;Database=XXX;PWD=XXX;SERVER=XXX;PORT=;UID=XXX;SSLmode=disable;ReadOnly=0;Protocol=7.4;FakeOidIndex=0;ShowOidColumn=0;RowVersioning=0;ShowSystemTables=0;Fetch=100;UnknownSizes=0;MaxVarcharSize=255;MaxLongVarcharSize=8190;Debug=0;CommLog=0;UseDeclareFetch=0;TextAsLongVarchar=1;UnknownsAsLongVarchar=0;BoolsAsChar=1;Parse=0;ExtraSysTablePrefixes=;LFConversion=1;UpdatableCursors=1;TrueIsMinus1=0;BI=0;ByteaAsLongVarBinary=1;UseServerSidePrepare=1;LowerCaseIdentifier=0;XaOpt=1"
    With ActiveSheet.QueryTables.Add(Connection:=connstring, _
        Destination:=Range("A1"), Sql:=sqlstring)
    .Refresh
    End With
End If