Gfilui

I hope someone can help. I've been at this for two days nearly and looked everywhere.

I ran BleachBit version 2.0 and now when I try and install anything with apt install it fails. I'm worried as I'm still quite new to Linux and where I should start trying to undo the damage.

My /etc/apt/sources.list looks like this:

#------------------------------------------------------------------------------#
# OFFICIAL UBUNTU REPOS #
#------------------------------------------------------------------------------#


###### Ubuntu Main Repos
deb http://au.archive.ubuntu.com/ubuntu/ xenial main restricted universe multiverse 

###### Ubuntu Update Repos
deb http://au.archive.ubuntu.com/ubuntu/ xenial-security main restricted universe multiverse 
deb http://au.archive.ubuntu.com/ubuntu/ xenial-updates main restricted universe multiverse 

###### Ubuntu Partner Repo
deb http://archive.canonical.com/ubuntu xenial partner

#------------------------------------------------------------------------------#
# UNOFFICIAL UBUNTU REPOS #
#------------------------------------------------------------------------------#


###### 3rd Party Binary Repos

#### Dropbox PPA - http://dropbox.com
## Run this command: sudo apt-key adv --keyserver pgp.mit.edu --recv-keys 5044912E
deb http://linux.dropbox.com/ubuntu/ xenial main

#### Gimp PPA - https://launchpad.net/~otto-kesselgulasch/+archive/gimp
## Run this command: sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 614C4B38
deb http://ppa.launchpad.net/otto-kesselgulasch/gimp/ubuntu xenial main

#### Steam for Linux - http://store.steampowered.com/about/
## Run this command: sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys F24AEA9FB05498B7
deb [arch=i386] http://repo.steampowered.com/steam/ precise steam

#### VirtualBox - http://www.virtualbox.org
## Run this command: wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox_2016.asc -O- | sudo apt-key add -
deb http://download.virtualbox.org/virtualbox/debian xenial contrib

My apt-cache stats output is as follows:

~$ apt-cache stats
Total package names: 4798 (96.0 k)
Total package structures: 5562 (245 k)
 Normal packages: 2624
 Pure virtual packages: 55
 Single virtual packages: 531
 Mixed virtual packages: 6
 Missing: 2346
Total distinct versions: 2635 (211 k)
Total distinct descriptions: 2722 (65.3 k)
Total dependencies: 21499/10512 (598 k)
Total ver/file relations: 2692 (64.6 k)
Total Desc/File relations: 2722 (65.3 k)
Total Provides mappings: 697 (16.7 k)
Total globbed strings: 11818 (208 k)
Total slack space: 29.3 k
Total space accounted for: 2,007 k
Total buckets in PkgHashTable: 50503
 Unused: 45916
 Used: 4587
 Utilization: 9.08263%
 Average entries: 1.21256
 Longest: 5
 Shortest: 1
Total buckets in GrpHashTable: 50503
 Unused: 45916
 Used: 4587
 Utilization: 9.08263%
 Average entries: 1.046
 Longest: 3
 Shortest: 1

This is a classic example of the error when I try and install ANYTHING:

sudo apt install htop
Reading package lists... Done
Building dependency tree 
Reading state information... Done
Package htop is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'htop' has no installation candidate

I've tried many things like:

• sudo apt-get clean


• sudo apt-get update


• getting a new sources.list online


• updating the sources.list from the update centre gui tool


• misc other bits n bobs

...all to no avail, I just keep getting the same error E: Package 'appName' has no installation candidate.

Can anyone offer some advice as to what to try next? I'm stumped and feeling a bit lost.