[ubuntu-uk] problem with synaptic- keeps closing down!!!

[Andrew Oakley]

Javad Ayaz wrote:
> 'E:Malformed line 40 in source list /etc/apt/sources.list (dist parse), 
> E:The list of sources could not be read.'! "

Your /etc/apt/sources.list file has become corrupt (maybe you added a 
new repository which wasn't valid, or edited it by hand?).

Please can you post your /etc/apt/sources.list file and we'll have a 
look. You can do this by going into Applications - Accessories - 
Terminal and typing:

cat /etc/apt/sources.list

...and then copy & paste. Also, which version of Ubuntu are you using? 
You can find this out by doing:

cat /etc/lsb-release

-- 
Andrew Oakley