Old code not working in 2010

Old version question here,

I can get this code to work in an older excel but I cannot get it to work in excel 2010.
Does anyone have any idea why it doesn't work?
The code pulls data from a closed file without opening it.

Sub DataFromClosedBook()
Dim mydata1 As String
mydata1 = "=c:\extract data\[r.xls]Sheet1'!$A$1:$A$10"
With ThisWorkbook.Worksheets(1).Range("a1:a10")
.Formula = mydata1
End With
End Sub

Any hints welcome

Kevin