synaptic still bonkers

[wayward4now]

Rats, still having problems with synaptic after I ripped Mint from the 
Natty install, like a screaming Mandrake root.

wayward4now at iam ~ $ sudo add-apt-repository ppa:mozillateam/thunderbird-next

Traceback (most recent call last):

   File "/usr/bin/add-apt-repository", line 60, in<module>

     sp = SoftwareProperties()

   File "/usr/lib/python2.7/dist-packages/softwareproperties/SoftwareProperties.py", line 90, in __init__

     self.reload_sourceslist()

   File "/usr/lib/python2.7/dist-packages/softwareproperties/SoftwareProperties.py", line 538, in reload_sourceslist

     self.distro.get_sources(self.sourceslist)

   File "/usr/lib/python2.7/dist-packages/aptsources/distro.py", line 91, in get_sources

     raise NoDistroTemplateException("Error: could not find a "

aptsources.distro.NoDistroTemplateException: Error: could not find a distribution template


Is there some sort of system install script that re-installs synaptic, 
after installation, to have these scripts back? Something had to run, 
during the initial install, to make those scripts happen. Thanks! Ric