我有 ubuntu 18.04 LTS，我想获得 BleachBit，当我尝试通过命令行时，我收到以下错误消息：
Preconfiguring packages ...
(Reading database ... 168709 files and directories currently installed.)
Removing linux-image-4.15.0-20-generic (4.15.0-20.21) ...
/etc/kernel/postrm.d/initramfs-tools:
update-initramfs: Deleting /boot/initrd.img-4.15.0-20-generic
/etc/kernel/postrm.d/zz-update-grub:
_XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
_XSERVTransMakeAllCOTSServerListeners: server already running
(EE)
Fatal server error:
(EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE)
(EE)
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE)
(EE) Server terminated with error (1). Closing log file.
run-parts: /etc/kernel/postrm.d/zz-update-grub exited with return code 1
dpkg: error processing package linux-image-4.15.0-20-generic (--remove):
installed linux-image-4.15.0-20-generic package post-removal script subprocess returned error exit status 1
Errors were encountered while processing:
linux-image-4.15.0-20-generic
E: Sub-process /usr/bin/dpkg returned an error code (1)
这是 Xorg.0.log 中的内容：
[ 2545.601] _XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
[ 2545.602] _XSERVTransMakeAllCOTSServerListeners: server already running
[ 2545.602] (EE)
Fatal server error:
[ 2545.603] (EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE)
[ 2545.603] (EE)
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
[ 2545.604] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[ 2545.604] (EE)
[ 2545.604] (EE) Server terminated with error (1). Closing log file.
我曾经sudo service lightdm stop尝试杀死 xserver 并得到“无法停止 lightdm.service：未加载单元 lightdm.service。”
当我尝试从网站安装时，我在通知中收到此错误消息：“无法安装 BleachBit：安装包时出错：安装的 linux-image-4.15.0-20-generic 包删除后脚本子进程返回错误退出状态1"
所以我在这里不知所措。当我查找错误消息时，我没有找到任何可以帮助我的东西。在尝试安装 ffmpeg 时，我也遇到了同样的命令行错误。我将不胜感激任何帮助。谢谢。
编辑：我去了 wiki.x.org，到https://www.x.org/wiki/FAQErrorMessages/，它说尝试netstat -ln但未找到命令 netstat，我在尝试安装时收到相同的错误消息.
EDIT2：cat /etc/apt/sources.list返回：
# deb cdrom:[Ubuntu 18.04 LTS _Bionic Beaver_ - Release amd64 (20180426)]/ bionic main restricted
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://us.archive.ubuntu.com/ubuntu/ bionic main restricted
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://us.archive.ubuntu.com/ubuntu/ bionic-updates main restricted
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-updates main restricted
## 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://us.archive.ubuntu.com/ubuntu/ bionic universe
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic universe
deb http://us.archive.ubuntu.com/ubuntu/ bionic-updates universe
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-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://us.archive.ubuntu.com/ubuntu/ bionic multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic multiverse
deb http://us.archive.ubuntu.com/ubuntu/ bionic-updates multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-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://us.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse
# deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe 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 bionic partner
# deb-src http://archive.canonical.com/ubuntu bionic partner
deb http://security.ubuntu.com/ubuntu bionic-security main restricted
# deb-src http://security.ubuntu.com/ubuntu bionic-security main restricted
deb http://security.ubuntu.com/ubuntu bionic-security universe
# deb-src http://security.ubuntu.com/ubuntu bionic-security universe
deb http://security.ubuntu.com/ubuntu bionic-security multiverse
deb http://archive.canonical.com/ bionic partner
# deb-src http://archive.canonical.com/ bionic partner
# deb-src http://security.ubuntu.com/ubuntu bionic-security multiverse
EDIT3：sudo dpkg --configure -a && sudo apt update --fix-missing -y && sudo apt install -f -y && sudo apt full-upgrade -y返回：
Setting up linux-image-4.15.0-29-generic (4.15.0-29.31) ...
Processing triggers for linux-image-4.15.0-29-generic (4.15.0-29.31) ...
/etc/kernel/postinst.d/initramfs-tools:
update-initramfs: Generating /boot/initrd.img-4.15.0-29-generic
/etc/kernel/postinst.d/zz-update-grub:
_XSERVTransSocketUNIXCreateListener: ...SocketCreateListener() failed
_XSERVTransMakeAllCOTSServerListeners: server already running
(EE)
Fatal server error:
(EE) Cannot establish any listening sockets - Make sure an X server isn't already running(EE)
(EE)
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
(EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
(EE)
(EE) Server terminated with error (1). Closing log file.
run-parts: /etc/kernel/postinst.d/zz-update-grub exited with return code 1
dpkg: error processing package linux-image-4.15.0-29-generic (--configure):
installed linux-image-4.15.0-29-generic package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
linux-image-4.15.0-29-generic
EDIT4：输出cat /etc/default/grub为：
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'
GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_idle.max_cstate=1"
GRUB_CMDLINE_LINUX=""
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"
# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"
X
sudo update-grub
X
X
sudo update-grub