Excel VBA Recordset is empty - sql-server

Question

i have an ADODB recordset to load data from a view in an Excel sheet. The view is located in a MS SQL database. It runs perfectly for months, but since a few days the recordset is always empty, so i did not get any results. After a long day searching the www for any reasons i found, that it can happen because i use a x32 Excel and there is so much data in the view. So i separated the procedure in two queries. This helped a lot and the macro run perfectly again. Yesterday the same error appears again, so i began to split the procedure again. But now the recordset is still empty. I don't know any reason for this. I tested it with a selection of only ten rows of the view and this runs but if i want to get 1000 rows the recordset is empty again. Does anybody know a reason for this problem? All queries give the result i want to have in the database so they are ok.
Here is my code:
Sub doStuff()
Dim sqlStatement(9) As String
Dim lrow As Long
'... other variables
sqlStatement(1) = "Select * from db.View1 where location like 'forest'"
'... other sqlStatements
For i = 0 To UBound(sqlStatement)
Call loadData(sqlStatement, lrow)
Next i
End Sub
Sub loadData(sqlStatement As String, lastrow As Long)
Dim sqlServer As String
Dim dbName As String
sqlServer = "MSSQLSERVER"
dbName = "database"
On Error Resume Next
Dim con As Object
Set con = CreateObject("ADODB.Connection")
con.Open _
"Provider = sqloledb;" & _
"Data Source=" & sqlServer & ";" & _
"Initial Catalog=" & dbName & ";" & _
"User ID=user1;" & _
"Password=abcde;"
Dim rst As Object
Set rst = CreateObject("ADODB.Recordset")
With rst
.ActiveConnection = con
.Open sqlStatement , con, adLockReadOnly
ws.Activate
If lastrow = 1 Then
For col = 0 To .Fields.Count - 1
ws.Cells(1, col + 1).Value = .Fields(col).Name
Next
End If
ws.Activate
ws.Cells(lastrow+1,1).CopyFromRecordset rst
.Close
End With
con.Close
Set rst = Nothing
Set con = Nothing
End Sub