Okay,
Tried copying the file as suggested. The ran clean-up and re-install but failed with the
same problem.
XML filed contains the following data
<network>
<name>default</name>
<uuid>ff26a6fe-c29c-433c-a99f-2d22724a73d4</uuid>
<forward mode='nat'/>
<bridge name='virbr0' stp='on' delay='0'/>
<mac address='52:54:00:ee:e3:0d'/>
<ip address='192.168.122.1' netmask='255.255.255.0'>
<dhcp>
<range start='192.168.122.2' end='192.168.122.254'/>
</dhcp>
</ip>
</network>