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When I run apt-get update on my Ubuntu 13.10 Desktop install I get this error:

W: Duplicate sources.list entry stable/main       amd64 Packages (/var/lib/apt/lists/
W: Duplicate sources.list entry stable/main i386 Packages (/var/lib/apt/lists/
W: You may want to run apt-get update to correct these problems

What does this mean? how can I resolve it? and what issues can it create? I want to understand the problem So if I run into it or anyone else I can help resolve it.

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marked as duplicate by Oli Nov 21 '13 at 12:46

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

See this Question. you can get a answer. – user224082 Nov 21 '13 at 12:44
up vote 18 down vote accepted

If means you've got the same source defined twice in your apt sources. It's a warning not an error. You could continue like this indefinitely if you wished.

To fix it, you just need to remove one of the definitions. To see all the definitions, run:

grep -R --include="*.list" chrome /etc/apt/

It's then just a case of editing (sudoedit filename) one of those out (either delete the line or comment it out by sticking a # at the beginning.

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Thanks again... – Daniel Toebe Nov 21 '13 at 13:42
@everyone else... Thanks all great answers – Daniel Toebe Nov 21 '13 at 13:42
perfect solution... – Abhishek Goel Feb 20 '14 at 9:06

First make sure about what arquitecture are you running and just remove the entry in Software Center>Edit>Sources or remove the line in your source list.

gksu gedit /etc/apt/sources.list

To find out your architecture

uname -a
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best answer. because you actually know what you are doing here – Nasz Njoka Sr. Nov 24 '15 at 7:17
This is called perfect answer. – Jigar Bhatt Mar 27 at 18:36

Its saying that you have duplicate lines in the /etc/apt/sources.list file. you have to remove those lines which were repeated.

type this command

sudo awk '!a[$0]++' /etc/apt/sources.list

it can delete the duplicate lines.

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