Unexpected crash after macro execution

Hi,
I have a macro which i need to run 10 times for different paths. The macros are the same excepting the "path_usr" and "file_usr". The macros needs to open another excel document, and replace the PROJECTS sheet from that document with the same named sheet form the first document. I do it in this way:

Sub copysheet_usr()


Dim w As Workbook
Dim path, page As String


page = "PROJECTS"
path = "\\192.168.0.6\path_usr\file_usr.xls"
Set w = Workbooks.Open(path)
w.Activate
For Each n In ActiveWorkbook.Names
n.Delete
Next n
Application.DisplayAlerts = False
w.Worksheets(page).Delete
Application.DisplayAlerts = True
Windows("file_usr.xls").Activate
Worksheets(page).Select
Worksheets(page).Copy Before:=w.Worksheets(1)
Application.DisplayAlerts = False
w.Close True
Application.DisplayAlerts = True

End Sub

This macro works without problems one time, but when i try to run it for the second user, it gives me the "Microsoft Excel has encoutered a problem and needs to close" error on the "Set w = Workbooks.Open(path)" step. Also if i simply close Microsoft Excel after the first macro execution i get the same error.
I can succesfully run each macro individually, but i need to restart Excel after every macro.
I have Microsoft Excel 2010 installed, on my Windows XP SP3, with no active add-ins in Excel.
It is very strange that sometimes i can run 2 or 3 macros before the crash, and if all the files are on the local computer, not on the network, it is no error at all.
If anyone can help me thanks in advance.