Some index files failed to download. They have been ignored, or old ones used instead [duplicate]

Question

I got below error while runing the command sudo apt-get update, I found similar questions but they do not help me. How do I fix this issue?

W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty/Release  Unable to find expected entry 'restricted/source/Sources' in Release file (Wrong sources.list entry or malformed file)

W: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/trusty/Release  Unable to find expected entry 'universe/source/Sources' in Release file (Wrong sources.list entry or malformed file)

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

cat /etc/apt/sources.list

# deb cdrom:[Ubuntu 14.04.4 LTS _Trusty Tahr_ - Release amd64 (20160217.1)]/ trusty main restricted
deb-src http://archive.ubuntu.com/ubuntu trusty main restricted #Added by software-properties

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://in.archive.ubuntu.com/ubuntu/ trusty main restricted
deb-src http://in.archive.ubuntu.com/ubuntu/ trusty universe restricted multiverse main #Added by software-properties

## Major bug fix updates produced after the final release of the
## distribution.
deb http://in.archive.ubuntu.com/ubuntu/ trusty-updates main restricted
deb-src http://in.archive.ubuntu.com/ubuntu/ trusty-updates universe restricted multiverse main #Added by software-properties

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://in.archive.ubuntu.com/ubuntu/ trusty universe
deb http://in.archive.ubuntu.com/ubuntu/ trusty-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://in.archive.ubuntu.com/ubuntu/ trusty multiverse
deb http://in.archive.ubuntu.com/ubuntu/ trusty-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://in.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://in.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse #Added by software-properties

deb http://security.ubuntu.com/ubuntu trusty-security main restricted
deb-src http://security.ubuntu.com/ubuntu trusty-security universe restricted multiverse main #Added by software-properties
deb http://security.ubuntu.com/ubuntu trusty-security universe
deb http://security.ubuntu.com/ubuntu trusty-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
deb http://archive.canonical.com/ubuntu trusty partner
deb-src http://archive.canonical.com/ubuntu trusty partner

## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
deb http://extras.ubuntu.com/ubuntu trusty main
deb-src http://extras.ubuntu.com/ubuntu trusty main
#deb http://us.archive.ubuntu.com/ubuntu precise main universe      

dig google.com

; <<>> DiG 9.9.5-3ubuntu0.7-Ubuntu <<>> google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 10513
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;google.com.            IN  A

;; ANSWER SECTION:
google.com.     52  IN  A   216.58.197.46
google.com.     52  IN  A   216.58.197.46
google.com.     52  IN  A   216.58.197.46

;; Query time: 9 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed May 17 20:17:42 IST 2017
;; MSG SIZE  rcvd: 87

I'm not seeing anything like http://archive.ubuntu.com/ubuntu/dists/trusty/Release in /etc/apt/sources.list actually where it is came from.

Can anyone suggest a way to solve this error please?

Answer 1

I compared your sources.list with one from a trusty machine of ours. Other than the country of origin of the servers, the big difference I saw was that your .list still contains the cdrom file. I remember removing this to solve some kind of problem, perhaps it was this?

Anyway, it is easy to test. Open "software & updates" and uncheck the last box. When you click Close, it will reload the sources, and tell you if it worked or not.