[Stable PPA] unmet dependencies installing nginx on 16.04 arm64

Can you please put in the output of the following command please as a comment to this question:

apt-cache policy nginx nginx-light nginx-extras nginx-full nginx-common

root@ubuntu:/# apt-cache policy nginx nginx-light nginx-extras nginx-full nginx-common
nginx:
  Installed: (none)
  Candidate: 1.10.1-0+xenial0
  Version table:
     1.10.1-0+xenial0 500
        500 http://ppa.launchpad.net/nginx/stable/ubuntu xenial/main arm64 Packages
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/main arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/main arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/main arm64 Packages
nginx-light:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-extras:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-full:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-common:
  Installed: 1.10.1-0+xenial0
  Candidate: 1.10.1-0+xenial0
  Version table:
 *** 1.10.1-0+xenial0 500
        500 http://ppa.launchpad.net/nginx/stable/ubuntu xenial/main arm64 Packages
        100 /var/lib/dpkg/status
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/main arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/main arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/main arm64 Packages

It appears that maybe this is a case of your system mis-handling the repository information.

I can confirm that there *are* versions of the packages in the PPAs; I would suggest perhaps just running apt-get one more time and seeing if that gets you more useful repository data.

I did apt-get update && apt-get upgrade and still get the same result

root@ubuntu:/# apt-get install nginx
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 nginx : Depends: nginx-full (>= 1.10.1-0+xenial0) but it is not going to be installed or
                  nginx-light (>= 1.10.1-0+xenial0) but it is not going to be installed or
                  nginx-extras (>= 1.10.1-0+xenial0) but it is not going to be installed
         Depends: nginx-full (< 1.10.1-0+xenial0.1~) but it is not going to be installed or
                  nginx-light (< 1.10.1-0+xenial0.1~) but it is not going to be installed or
                  nginx-extras (< 1.10.1-0+xenial0.1~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
root@ubuntu:/# apt-get upgrade apt
Reading package lists... Done
Building dependency tree
Reading state information... Done
apt is already the newest version (1.2.12~ubuntu16.04.1).
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

root@ubuntu:/# apt-cache policy nginx nginx-light nginx-extras nginx-full nginx-common
nginx:
  Installed: (none)
  Candidate: 1.10.1-0+xenial0
  Version table:
     1.10.1-0+xenial0 500
        500 http://ppa.launchpad.net/nginx/stable/ubuntu xenial/main arm64 Packages
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/main arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/main arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/main arm64 Packages
nginx-light:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-extras:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-full:
  Installed: (none)
  Candidate: 1.10.0-0ubuntu0.16.04.2
  Version table:
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/universe arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/universe arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/universe arm64 Packages
nginx-common:
  Installed: 1.10.1-0+xenial0
  Candidate: 1.10.1-0+xenial0
  Version table:
 *** 1.10.1-0+xenial0 500
        500 http://ppa.launchpad.net/nginx/stable/ubuntu xenial/main arm64 Packages
        100 /var/lib/dpkg/status
     1.10.0-0ubuntu0.16.04.2 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial-updates/main arm64 Packages
        500 http://ports.ubuntu.com/ubuntu-ports xenial-security/main arm64 Packages
     1.9.15-0ubuntu1 500
        500 http://ports.ubuntu.com/ubuntu-ports xenial/main arm64 Packages

Whoops, looks like the PPA where these actually build (not the ppa you add to your repository sources) doesn't have arm64 builds. Guess it's time to start including them. I'll have to make some arm64 builds first and copy them over.

This issue should now be resolved, as I have put arm64 builds into the Stable PPA now.

Thanks Thomas. I successfully installed the stable ppa on an arm64 16.04 platform

I encounter a similar issue as described above when trying to install it for amd64. (Version 1.10.3-0)
The output of apt-cache policy nginx nginx-light nginx-extras nginx-full nginx-common:

nginx:
  Installed: (none)
  Candidate: 1.10.3-0+trusty0
  Version table:
     1.10.3-0+trusty0 0
        500 http://ppa.launchpad.net/nginx/stable/ubuntu/ trusty/main amd64 Packages
     1.1.19-1 0
        500 http://archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
nginx-light:
  Installed: (none)
  Candidate: 1.10.3-0+trusty0
  Version table:
     1.10.3-0+trusty0 0
        500 http://ppa.launchpad.net/nginx/stable/ubuntu/ trusty/main amd64 Packages
     1.1.19-1 0
        500 http://archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
nginx-extras:
  Installed: (none)
  Candidate: 1.10.3-0+trusty0
  Version table:
     1.10.3-0+trusty0 0
        500 http://ppa.launchpad.net/nginx/stable/ubuntu/ trusty/main amd64 Packages
     1.1.19-1 0
        500 http://archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
nginx-full:
  Installed: (none)
  Candidate: 1.10.3-0+trusty0
  Version table:
     1.10.3-0+trusty0 0
        500 http://ppa.launchpad.net/nginx/stable/ubuntu/ trusty/main amd64 Packages
     1.1.19-1 0
        500 http://archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
        100 /var/lib/dpkg/status
nginx-common:
  Installed: (none)
  Candidate: 1.10.3-0+trusty0
  Version table:
     1.10.3-0+trusty0 0
        500 http://ppa.launchpad.net/nginx/stable/ubuntu/ trusty/main amd64 Packages
     1.1.19-1 0
        500 http://archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
        100 /var/lib/dpkg/status

The error message when trying to install nginx:

Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 nginx : Depends: nginx-full (< 1.10.3-0+trusty0.1~) but it is not going to be installed or
                  nginx-light (< 1.10.3-0+trusty0.1~) but it is not going to be installed or
                  nginx-extras (< 1.10.3-0+trusty0.1~) but it is not going to be installed
         Depends: nginx-full (>= 1.10.3-0+trusty0) but it is not going to be installed or
                  nginx-light (>= 1.10.3-0+trusty0) but it is not going to be installed or
                  nginx-extras (>= 1.10.3-0+trusty0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Is this linked to the issue above?