Try this code
Code:
Set olapp = CreateObject("Outlook.Application")
Set olns = olapp.GetNameSpace("MAPI")
olns.logon
Set objfolder=olns.getdefaultfolder(6)
objfolder.display
set msg = olapp.createitem(olMailitem)
Set rcp = msg.recipients.Add ("xxx@gmail.com")
msg.subject = "Automated mail from QTP - Result "
msg.body = "XXXXXXXXXXXXXXX"
msg.Attachments.Add ("Z:\Sample.xls")
msg.send