Unable to export vm

[abdulazizyaakup]

I'm trying to move all my vm from server1 to new server2. I want to export VM as backup into my local machine before import it to server2. But this error occur:

Export snap as VM..
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/openxenmanager-0.1b1-py2.7.egg/OXM/window.py", line 1443, in on_btsavefile_activate
self.xc_servers[self.selected_host].export_vm(self.selected_snap_ref, filechooser.get_filename(),
AttributeError: 'oxcWindow' object has no attribute 'selected_snap_ref'

Can anyone help on this.