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Possible Duplicate:
How can I fix a 404 Error using a PPA?

I can't remove the red triangle in the right upper corner of my desktop. When I type sudo apt-get update && sudo apt-get upgrade I get the error message below:

W: Failed to fetch  404  Not Found

W: Failed to fetch  404  Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.

How to fix my problem?

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marked as duplicate by Jorge Castro, Tom Brossman, fossfreedom Dec 26 '12 at 0:00

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.

... and your question is? I assume you want these errors 404 fixed? – Rinzwind Aug 27 '12 at 7:23
up vote 3 down vote accepted

Have a look at your /etc/apt/sources.list and remove (or fix) those two lines that cause the error 404. After removing the update process can be started again and it will continue updating.

Canon printer driver precise

This PPA does not contain any packages yet. Find more information about how to upload packages in the PPA help page.

This is probably the cause for the error 404 (non existing URL).

There is also:

  • Canon printer driver daily.

    deb precise main 
    deb-src precise main 

But I am not sure if this is what you need.

It could also be this that you need:

Though these only seem valid for Oneiric.

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Thanks it works properly. I will observe it in 3 days to make sure the red triangle will not appear again. – user85821 Aug 28 '12 at 13:01
excellent @user85821 .As long as your source list is OK the red triangle shall not return ;-) – Rinzwind Aug 28 '12 at 13:08

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