Update Manager can't set LC_MESSAGES to default locale

I doubt this problem was there in old versions of Ubuntu. When I run terminal command I got the following reply

rm: cannot remove `/var/lib/apt/lists/lock': No such file or directory.

It is sure.......I can't see any 'lock' in /lists/........The only folder in 'lists' is an empty 'partial' folder.

What should I do next

I suspect that <http://askubuntu.com/q/759795> is related. In that case LANG is set to "en_IN", which is a perfectly valid name of the English/India UTF-8 locale.

$ cat /usr/share/i18n/SUPPORTED | grep en_IN
en_IN UTF-8

Changing LANG to "en_IN.UTF-8" makes the error messages go away.

So there seems to be an incorrect locale validity test somewhere in the code.

This bug is still present in Xenial, version 1:16.04.3.

Possibly related to https://bugs.python.org/issue20087

I'm having the problem, or a similar one, on Linux Mint 18.1 Serena XFCE, which is based on Xenial.

My version of this problem affects many programs, not just update-manager:

man: can't set the locale; make sure $LC_* and $LANG are correct

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
 LANGUAGE = (unset),
 LC_ALL = (unset),
 LANG = "en_US"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").

"pip" doesn't run at all. locale.Error: unsupported locale setting

So I did: (% is the shell prompt)

% locale
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_US
LANGUAGE=
LC_CTYPE="en_US"
LC_NUMERIC="en_US"
LC_TIME="en_US"
LC_COLLATE="en_US"
LC_MONETARY="en_US"
LC_MESSAGES="en_US"
LC_PAPER="en_US"
LC_NAME="en_US"
LC_ADDRESS="en_US"
LC_TELEPHONE="en_US"
LC_MEASUREMENT="en_US"
LC_IDENTIFICATION="en_US"
LC_ALL=
% grep en_US /usr/share/i18n/SUPPORTED
en_US.UTF-8 UTF-8
en_US ISO-8859-1
en_US.ISO-8859-15 ISO-8859-15
% LANG=en_US.UTF-8
% man {some program}
# Now the error message isn't displayed! -- and likewise in programs that use Perl.

I'm having the issue with en_US (no other locale has ever been selected in this OS install), *not* one of the locales mentioned in the linked bug-report https://bugs.python.org/issue20087

I was getting the same error messages in Linux Mint Debian Edition 2 "Betsy", which is based on Debian stable/jessie. I can do a little more testing on that OS install if it's relevant to this bug report.

I searched on Launchpad for similar issues, but this one I'm commenting in is the closest one I've found.

Of course, I can put a file in /etc/profile.d/ to set LANG=en_US.UTF-8 when anyone logs in, but I hope a bug report has been, or will be, filed against the relevant package.

Please let me know if there is a more appropriate bug report I should monitor and/or comment in.

@dg1727: I don't think you encountered a bug at all; you just have set an incorrect locale name. "en_US" isn't generated by default, and if it is present, it enables latin1 encoding, which you probably not want. Just update /etc/default/locale by running this command:

sudo update-locale LANG=en_US.UTF-8

In my case, the problem was a file ~/.dmrc which was as follows:

[Desktop]
Language=en_US
Langlist=en_US:en
LCMess=en_US.UTF-8
Layout=us
Session=xfce

Deleting that .dmrc file fixed the issue.

Neither the user of this user account, nor the admin user, has ever explicitly set a locale to en_US. So apparently there was a bug in a previous software version that produced the "en_US". (The same /home partition is being used as when a previous distro was running on the machine.)

@dg1727: I see. Good that you figured it out.

The entries in that ~/.dmrc file might have been set by a very old version of GDM. So yes, it may be some kind of old transition bug between different versions and/or different display managers. I'd suggest that we leave it at that.