Here is the complete mail.log  Jul 14 16:48:20 rezocoquin sendmail[5861]: v6EEmKCT005861: from=www-data, size=194, class=0, nrcpts=1, msgid=&lt;201707141448.v6EEmKCT005861@rezocoquin.com&gt;, relay=www-data@localhost Jul 14 16:48:20 rezocoquin sm-mta[5863]: v6EEmKvf005863: from=&lt;www-data@rezocoquin.com&gt;, size=419, class=0, nrcpts=1, msgid=&lt;201707141448.v6EEmKCT005861@rezocoquin.com&gt;, proto=ESMTP, daemon=MTA-v4, relay=rezocoquin.com [127.0.0.1] Jul 14 16:48:20 rezocoquin sendmail[5861]: v6EEmKCT005861: to=yarekc@gmail.com, ctladdr=www-data (33/33), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30194, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (v6EEmKvf005863 Message accepted$ Jul 14 16:48:20 rezocoquin sm-mta[5868]: STARTTLS=client, relay=gmail-smtp-in.l.google.com., version=TLSv1/SSLv3, verify=FAIL, cipher=ECDHE-RSA-AES128-GCM-SHA256, bits=128/128 Jul 14 16:48:20 rezocoquin sm-mta[5868]: v6EEmKvf005863: to=&lt;yarekc@gmail.com&gt;, ctladdr=&lt;www-data@rezocoquin.com&gt; (33/33), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=120419, relay=gmail-smtp-in.l.google.com. [IPv6:2a00:1450:400c:c07::1b], d$ Jul 14 16:48:20 rezocoquin sm-mta[5868]: v6EEmKvf005863: v6EEmKvf005868: DSN: Service unavailable Jul 14 16:48:21 rezocoquin sm-mta[5868]: v6EEmKvf005868: to=&lt;www-data@rezocoquin.com&gt;, delay=00:00:01, xdelay=00:00:00, mailer=local, pri=30000, dsn=2.0.0, stat=Sent   -> No email is received: any idea ?
I've been having trouble getting my server to send email and I haven't for the life of me figured out how to fix it. If anyone could give me some simple pointers, that would be muchly appreciated!  May 19 15:36:03 ubuntu-12 sm-mta[2484]: s4JFa3jp002484: from=&lt;www-data@ubuntu-12.04-     production&gt;, size=412, class=0, nrcpts=1, msgid=&lt;201405191535.s4JFZw4c002483@ubuntu-12.04-  production&gt;, proto=ESMTP, daemon=MTA-v4, relay=ip6-localhost [127.0.0.1] May 19 15:36:03 ubuntu-12 sendmail[2483]: s4JFZw4c002483: to=myname@mycompany.com, ctladdr=www-data (33/33), delay=00:00:05, xdelay=00:00:05, mailer=relay, pri=30123, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (s4JFa3jp002484 Message accepted for delivery) May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002484: to=&lt;myname@mycompany.com&gt;, ctladdr=&lt;www-data@ubuntu-12.04-production&gt; (33/33), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=120412, relay=mailserver.mycompany.com. [213.171.216.115], dsn=5.0.0, stat=Service unavaila$ May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002484: s4JFa3jp002487: DSN: Service unavailable May 19 15:36:03 ubuntu-12 sm-mta[2487]: s4JFa3jp002487: to=&lt;www-data@ubuntu-12.04-production&gt;, delay=00:00:00, xdelay=00:00:00, mailer=local, pri=30000, dsn=2.0.0, stat=Sent
Help with proof that $\mathbb Z[i]/\langle 1 - i \rangle$ is a field. ls command operating differently depending on recipient How does commands like ls know what its stdout is?  It seems ls is operating different depending on what the target stdout is. For example if I do:  ls /home/matt/tmp    the result is:  a.txt b.txt c.txt   However if I do  ls /home/matt/tmp | cat   the result is (i.e. new line per result):  a.txt b.txt c.txt   The process is passed a file descriptor 1 for stdout right? How does it determine how to format the result? Does the file descriptor reveal information? Is Ubuntu an open source software? Energy-momentum tensor transformation On Cesàro convergence: If $ x_n \to x $ then $ z_n = \frac{x_1 + \dots +x_n}{n} \to x $ I have this problem I'm working on. Hints are much appreciated (I don't want complete proof):  In a normed vector space, if $ x_n \longrightarrow x $ then  $ z_n = \frac{x_1 + \dots +x_n}{n} \longrightarrow x $   I've been trying adding and subtracting inside the norm... but I don't seem to get anywhere.  Thanks! How do I set up a global locale for the computer?  I have recently installed Kubuntu 14.04LTS in english but since I am in Spain, I chose Spain as a country and then changed locale options so that I get all country specific configuration such as digit grouping, decimal separator, date format, etc. I also added the spanish language.  Now all applications complain that locale is wrong. check-language-support tells me I'm using en_ES.UTF-8 as system's locale, and that locale is indeed wrong, there is no locale for english language in Spain.  I tried using Kubuntu's country/region &amp; language settings but it doesn't fix it. I tried using export LANG=en_GB.UTF-8 and export LC_ALL=en_GB.UTF-8 and then sudo dpkg-reconfigure locales and that caused check-language-support to say that I now have a correct configuration but if it is, it's only in that konsole session. This problem also prevents konsole from showing unicode characters and I cannot use dead keys or enter any 'international character' such as ñ or ç (those work on other applications such as Firefox, that I'm using to post this question).  So the question is: How do I set up a global locale for the computer?  This is not a bug report, I will probably reinstall my computer eventually if I can't fix it. But I really want to know how I can perform this REALLY basic task.  Thank you.  $ check-language-support perl: warning: Setting locale failed. perl: warning: Please check that your locale settings:         LANGUAGE = "en:es:en",         LC_ALL = (unset),         LC_PAPER = "en_ES.UTF-8",         LC_ADDRESS = "en_ES.UTF-8",         LC_MONETARY = "en_ES.UTF-8",         LC_NUMERIC = "en_ES.UTF-8",         LC_TELEPHONE = "en_ES.UTF-8",         LC_IDENTIFICATION = "en_ES.UTF-8",         LC_MEASUREMENT = "en_ES.UTF-8",         LC_TIME = "en_ES.UTF-8",         LC_NAME = "en_ES.UTF-8",         LANG = "en_ES.UTF-8"     are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). 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_COLLATE to default locale: No such file or directory hunspell-en-ca libreoffice-help-en-gb libreoffice-l10n-en-gb libreoffice-l10n-en-za mythes-en-au wspanish  $ cat /etc/default/locale LANG="en_US.UTF-8" LC_NUMERIC="es_ES.UTF-8" LC_TIME="es_ES.UTF-8" LC_MONETARY="es_ES.UTF-8" LC_PAPER="es_ES.UTF-8" LC_NAME="es_ES.UTF-8" LC_ADDRESS="es_ES.UTF-8" LC_TELEPHONE="es_ES.UTF-8" LC_MEASUREMENT="es_ES.UTF-8" LC_IDENTIFICATION="es_ES.UTF-8"   $ 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_ES.UTF-8 LANGUAGE=en:es:en LC_CTYPE="en_ES.UTF-8" LC_NUMERIC=en_ES.UTF-8 LC_TIME=en_ES.UTF-8 LC_COLLATE="en_ES.UTF-8" LC_MONETARY=en_ES.UTF-8 LC_MESSAGES="en_ES.UTF-8" LC_PAPER=en_ES.UTF-8 LC_NAME=en_ES.UTF-8 LC_ADDRESS=en_ES.UTF-8 LC_TELEPHONE=en_ES.UTF-8 LC_MEASUREMENT=en_ES.UTF-8 LC_IDENTIFICATION=en_ES.UTF-8 LC_ALL= $ update-locale perl: warning: Setting locale failed. perl: warning: Please check that your locale settings:         LANGUAGE = "en:es:en",         LC_ALL = (unset),         LC_PAPER = "en_ES.UTF-8",         LC_ADDRESS = "en_ES.UTF-8",         LC_MONETARY = "en_ES.UTF-8",         LC_NUMERIC = "en_ES.UTF-8",         LC_TELEPHONE = "en_ES.UTF-8",         LC_IDENTIFICATION = "en_ES.UTF-8",         LC_MEASUREMENT = "en_ES.UTF-8",         LC_TIME = "en_ES.UTF-8",         LC_NAME = "en_ES.UTF-8",         LANG = "en_ES.UTF-8"     are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). Change font of formula number in DisplayFormulaNumbered Is there a way to install a newer version than in the repository?  Ubuntu installs vagrant 1.4.3 at the moment, but I need at least 1.5 How to add a custom field to the media screen (image/gallery)? I’m trying to add a custom field to image and gallery edit screen.  I’m aware there are similar questions here, although answers either don’t work with the current version or they add field only to upload screen while I need a field to be visible in all edit screens (see below).  For this, I believe, you’ll have to mess with backbone.js as attachment_fields_to_edit only adds to upload screen.  Adding field with attachment_fields_to_edit    ↑ This is upload image screeen. Here Style is added with attachment_fields_to_edit filter, and my_field is added with ACF plugin.   But they are missing in edit screen in the post    ↑ Click edit on the actual post    ↑ No style &amp; my_field fields!  The question  How to add fields to still have them on the edit screen? Ideally answer will include adding fields to gallery edit screen if it’s a similar process  This question is really important for me so I’ll be adding a 100 rep bounty when it’s available.   Thanks! Editing PostGIS/GeoServer data via web? I've got PostGIS installed and would like to create a web application to do some simple edits:   Draw manually (over a Basemap) points, lines and polylines, using snapping  points (points, end of lines, intersections, center of circles)  Delete points, lines and polylines  Rotate a line or group of lines around a point  Move a line or group of lines with a base point  Move polylines and points (manually and to a point given by the coordinates) Edit position of vertices of polylines and lines (manually and to a point given by the coordinates)  Create buffers around points, lines and polylines    Which is the best way to do this via web? Is there any already-built JavaScript library? Let $\{x_n\}$ and $\{y_n\}$ be sequences of real numbers which converge to $\ell$ and $m$ respectively. Show that  $$\lim_{n\to \infty} \frac{1}{n}\sum_{k=1}^{n}x_ky_{n+1-k}=\ell m$$  This is a problem I found in a book, it seemed to be routine, but now I can't solve it.  What I tried :     Let us take some $\epsilon&gt;0$. Now after a stage $N$, both $|x_n-\ell|&lt;\epsilon$ and $|y_n-m|&lt;\epsilon$. Now I wanted to break the sum $$\left|\frac{1}{n}\sum_{k=1}^{n}x_ky_{n+1-k}-\ell m\right|$$in two parts, one upto $N$, and other one for $N+1$ to $n$. Now we need this to be arbitrarily small. But here I am lost. I don't know how to proceed anymore. Because when I take $x_i's$ to make up a finite sum, then the $y_j's$ are there too with $j$ very large. I think this is the main idea, but unable to do anything further. Can someone help me? Thanks. Is it possible to take an image from the clipboard and output it to a file (using X)?  I can do this with text easily:  $ xclip -selection c -o &gt; file.text   But when I try the above with an image nothing is written.    The reason I want to do this is I don't have an image editor installed, and it got me thinking whether I could do this without installing one. Why does a RegExp with global flag give wrong results? Is sun revolving around certain mass in space with reference to some other galaxy? Let a be a positive number. Then $\lim_{n \to \infty}[\frac{1}{a+n}+\frac{1}{2a+n}+\cdots +\frac{1}{na+n}]$ Minecraft item right/left click detection I'm setting up an online ordering system but I'm in Australia and for international customers I'd like to show prices in US dollars or Euros so they don't have to make the mental effort to convert from Australian dollars.  Does anyone know if I can pull up to date exchange rates off the net somewhere in an easy-to-parse format I can access from my PHP script ?    UPDATE: I have now written a PHP class which implements this. . Orthogonal projections with $\sum P_i =I$, proving that $i\ne j \Rightarrow  P_{j}P_{i}=0$ Best way to return multiple values from a function? When I install Selenium I get the following error:  Shubham@Shubham-To-be-filled-by-O-E-M:~$ sudo apt-get update     Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [107 kB]     Hit:2 https://repo.skype.com/deb stable InRelease                            Hit:3 http://in.archive.ubuntu.com/ubuntu xenial InRelease                          Get:4 http://in.archive.ubuntu.com/ubuntu xenial-updates InRelease [109 kB]     Get:5 http://in.archive.ubuntu.com/ubuntu xenial-backports InRelease [107 kB]       Fetched 323 kB in 8s (38.6 kB/s)                                                    Reading package lists... Done     Shubham@Shubham-To-be-filled-by-O-E-M:~$ sudo pip install selenium     Traceback (most recent call last):       File "/usr/bin/pip", line 9, in &lt;module&gt;         from pip import main     ImportError: cannot import name main   How should I proceed?