Linux Mint 17 synoptic update manager

[joe at actionline.com]

In mid-November, I first posted a question about the
subject problem, and the problem remains unresolved.
Below is a copy of a follow-up question I posted Dec 1.

Every time I open the Synaptic update manager, the
problem has gotten worse, to the point that now the
upper frame is completely closed so that no text that
might be in that frame can be seen. Here are three
successive screen shots of this problem:

>From Nov 18: http://www.upquick.com/temp/updatemanager1.jpg
>From Dec 01: http://www.upquick.com/temp/updatemanager2.jpg
>From Dec 11: http://www.upquick.com/temp/updatemanager3.jpg

Certainly do hope that someone can help me solve this mystery.


----------------------
Larry Lauer last wrote:
> Could have a look at
> https://www.unixmen.com/quick-tip-fix-gpg-error-badsig-linux-mint-ubuntu/

------------------
To which I replied:
Thanks Larry.  I had found and already done all the steps
described in the unixmen article ... and that did help to
resolve most of the problems that I had reported.  However,
the problem with the synaptic Update Manager page as shown
in the screen shot that I had provided remains unresolved.

So I have now added a newer screen shot that shows how the
problem has gotten even worse -- so bad that it is now
impossible to see any content that may be in that top window.

http://upquick.com/temp/synaptic1b.jpg (since renamed)

--------------
>> On Dec 1, 2016, at 2:38 AM, joe wrote (in part):
>> ... the problem with the top window in the synaptic
>> "Update Manager" (as shown in the screen shot link below)
>> has gotten even worse (the window gets smaller and smaller
>> every time I open synaptic), to the point that this top
>> window is now so small that nothing that might be in that
>> window can even be seen.
>>
>> http://upquick.com/temp/synaptic1.jpg (since renamed)
>>
>> What can I do to fix this problem?

PS: I have done all these steps:
$ sudo -i
# apt-get clean
# cd /var/lib/apt
# mv lists lists.old
# mkdir -p lists/partial
# apt-get clean
# apt-get update