The tutorial you sent seems to be for Debian.  Mine is on Ubuntu.  I checked that document and changed it to TLSv1.2.  There is nothing related to "stats".  Im still getting the same error.

DO you have any document for upgrade on Ubuntu?

I tried to update the "Sogo" but it failed.
*************************************************
dpkg-deb: error: paste subprocess was killed by signal (Broken pipe)
Selecting previously unselected package memcached.
Preparing to unpack .../4-memcached_1.5.6-0ubuntu1.1_amd64.deb ...
Unpacking memcached (1.5.6-0ubuntu1.1) ...
Selecting previously unselected package sogo-common.
Preparing to unpack .../5-sogo-common_3.2.10-1build1_all.deb ...
Unpacking sogo-common (3.2.10-1build1) ...
Selecting previously unselected package zip.
Preparing to unpack .../6-zip_3.0-11build1_amd64.deb ...
Unpacking zip (3.0-11build1) ...
Selecting previously unselected package sogo.
Preparing to unpack .../7-sogo_3.2.10-1build1_amd64.deb ...
Unpacking sogo (3.2.10-1build1) ...
Errors were encountered while processing:
/tmp/apt-dpkg-install-xaSxIl/3-libsope1_3.2.10-1build1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
**************************************************************************

var/log

**********************************************************

==> /var/log/kern.log.1 <==
Aug  9 17:29:01 mail kernel: [   12.387182] new mount options do not match the existing superblock, will be ignored
Aug  9 17:29:01 mail kernel: [   12.928289] kauditd_printk_skb: 8 callbacks suppressed
Aug  9 17:29:01 mail kernel: [   12.928291] audit: type=1400 audit(1565371741.740:20): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=1413 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
Aug  9 17:29:01 mail kernel: [   13.117650] audit: type=1400 audit(1565371741.928:21): apparmor="DENIED" operation="open" profile="/usr/bin/freshclam" name="/etc/ssl/openssl.cnf" pid=1336 comm="freshclam" requested_mask="r" denied_mask="r" fsuid=0 ouid=0
Aug  9 17:29:01 mail kernel: [   13.157364] audit: type=1400 audit(1565371741.968:22): apparmor="DENIED" operation="open" profile="/usr/sbin/clamd" name="/etc/ssl/openssl.cnf" pid=1403 comm="clamd" requested_mask="r" denied_mask="r" fsuid=114 ouid=0
Aug  9 17:29:02 mail kernel: [   13.356607] audit: type=1400 audit(1565371742.168:23): apparmor="DENIED" operation="capable" profile="/usr/sbin/mysqld" pid=1413 comm="mysqld" capability=2  capname="dac_read_search"
Aug  9 17:29:02 mail kernel: [   13.491566] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
Aug  9 17:29:02 mail kernel: [   13.728845] audit: type=1400 audit(1565371742.540:24): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=1544 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=112 ouid=0
Aug  9 17:29:15 mail kernel: [   27.119705] random: crng init done
Aug  9 17:29:15 mail kernel: [   27.119709] random: 7 urandom warning(s) missed due to ratelimiting

==> /var/log/kern.log.2.gz <==
P?Xd 9?Ԏ?"?p???w᦮5J&ls???Vbh    ??????`L?|?v?[????[?k??Ŧ?Cto??!???h"?$]&?0F&)?4w-[
  miNi?yo`+Y'?v??1Sx???BN?>&?~???I??    ?JM,n?{yq
                                                 O?!D??׹a?d?×??YB???/?P?$???s?o4Aʪ? IC3"E?꾝?D(i=?޹;?E??U???B4???њ???e?E?y2
                                           {}jW????&??,??YO????rlg/??!?????k2??de??ɘ?q???64&?? <,???A6?AMb???????a?
                                   R?y??)?)&??rM+j??(?cqs}!????'??;?~jum
yޥs?6ɗ?>^????0ލ???=ҨR?x????M????????R????0
??H??KAM?6I:m??
GR?m?f`/%???E8??΁?&޼???(?e?????5?P?lr???;??P .?B?;??????;]J
??a?~?????
?*a?+2ϭ?x??,\FP???gL?)|?p
???f?Y?:͒^k?ө?*w@???y??0y??$&?l????x!??Z??

==> /var/log/auth.log <==
Aug 11 18:45:44 mail sshd[649]: rexec line 19: Deprecated option KeyRegenerationInterval
Aug 11 18:45:44 mail sshd[649]: rexec line 20: Deprecated option ServerKeyBits
Aug 11 18:45:44 mail sshd[649]: rexec line 31: Deprecated option RSAAuthentication
Aug 11 18:45:44 mail sshd[649]: rexec line 38: Deprecated option RhostsRSAAuthentication
Aug 11 18:45:44 mail sshd[649]: reprocess config line 31: Deprecated option RSAAuthentication
Aug 11 18:45:44 mail sshd[649]: reprocess config line 38: Deprecated option RhostsRSAAuthentication
Aug 11 18:45:44 mail sshd[649]: Accepted publickey for root from 47.189.84.3 port 49356 ssh2: RSA SHA256:slCtLll0OsQ2v6ez6h/83T7+QXkin7HRA6l83z8ROAs
Aug 11 18:45:44 mail sshd[649]: pam_unix(sshd:session): session opened for user root by (uid=0)
Aug 11 18:45:44 mail systemd: pam_unix(systemd-user:session): session opened for user root by (uid=0)
Aug 11 18:45:44 mail systemd-logind[1391]: New session 3763 of user root.

==> /var/log/auth.log.1 <==
Aug  4 06:21:02 mail CRON[13577]: pam_unix(cron:session): session closed for user sogo
Aug  4 06:22:01 mail CRON[13581]: pam_unix(cron:session): session opened for user sogo by (uid=0)
Aug  4 06:22:01 mail CRON[13581]: pam_unix(cron:session): session closed for user sogo

==> /var/log/auth.log.2.gz <==
??ѻ?=???~???7b??ݻ?=:W1?ݯ????o?s??Nv???F?rb???Ov?Ng?b?????????c???fq1і2?=;??\?Z.~?d???=p?{?s?Ej?j'??Vڄ%8ٽ?9V8?
/?&?K-Z-..ڽ#<???!????C!2????v??V?r;??@?=??C
??j?!?7l!?`???????AOj?'[\zE˪et5??-?
??%8??z?+Z>??{??-?
?=?lq=Qw???~Ūp?Ŕ??+??l??7???lI?7??"et5??-eb'Z":$_???{H???E??????????k?}?̈́D??.?!??~p??Ʌ???Nvo.?\l
?T??Nvo؎31????s&8ٽ7ɺ?Lr??e^???z???LG????F{??`
                                         ???