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I am getting a problem in Ubuntu as an error opening the cache, the list of software sources could not be read in my /etc/apt/sources.list file and the package lists or status file could not be parsed or opened. I am new to Ubuntu, so I could not determine what is causing the problem. I also have a problem opening the Ubuntu Software Center and once I commented out line no. 56 stating deb partner, Ubuntu Software Center opens OK. What could the problem be? I am including 4 lines from my sources.list file.

Source.list code on my line 56 is this:

deb partner
# deb-src partner  
# deb-src partner
# deb-src partner

Terminal output:

Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/gi/overrides/", line 629, in <lambda>
return (lambda data: callback(*data), user_data)
File "/usr/share/software-center/softwarecenter/db/pkginfo_impl/", line   261, in open
self._cache = apt.Cache(progress)
File "/usr/lib/python2.7/dist-packages/apt/", line 105, in __init__
File "/usr/lib/python2.7/dist-packages/apt/", line 150, in open
self._cache = apt_pkg.Cache(progress)
SystemError: E:Malformed line 56 in source list /etc/apt/sources.list (dist parse),       E:The list of sources could not be read., E:The package lists or status file could not be parsed or opened.
2014-01-22 11:27:29,685 - softwarecenter.db.pkginfo_impl.aptcache - INFO -
share|improve this question
Try to open software center via terminal and then post its output. – Avinash Raj Jan 22 '14 at 5:54
terminal output added – minu Jan 22 '14 at 6:01
uncomment the 56th line in sources.list.Then open software center via terminal and post it's output. – Avinash Raj Jan 22 '14 at 6:03
1st line in my source.list code is line no 56 it's already uncommented after uncommenting I'm getting this error – minu Jan 22 '14 at 6:05
then delete the first line(which was same as 56th) from sources.list. – Avinash Raj Jan 22 '14 at 6:07
up vote 0 down vote accepted

Since you made changes to the sources, you should update the apt so that the changes are recognized.

To do that, open a terminal (press Ctrl + Alt + T) and enter the command:

sudo apt-get update

and you should be done.

share|improve this answer
this worked for me thank you – minu Jan 22 '14 at 6:27
glad it helped.. and welcome to AskUbuntu... – precise Jan 22 '14 at 6:29

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