ADO To Retrieve Data From One Sheet Into Another Sheet

I am using ADO to retrieve data from sheet 1 and 2 into sheet 3, within the same workbook.

The following code does the job correctly.

However, when I have two such workbooks open, say workbook 1 and 2 and run the code separately to retrieve data into sheet 3 of workbook 1 (from sheets 1 and 2 of workbook 1) and retrieve data into sheet 3 of workbook 2 (from sheets 1 and 2 of workbook 2), I get a runtime error message.

I suspect it might have something to do with locking: rs.LockType = adLockOptimistic

Sub Get_Data
Dim cn As ADODB.Connection
Dim rs As ADODB.Recordset
Set cn = New ADODB.Connection
Set rs = New ADODB.Recordset

[Code]....