After I sudo apt-get install mono-devel , when I try to purge mono-devel on Ubuntu Linux 16.04, I get the following error message:
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:
mono-devel : Depends: mono-runtime (>= 2.10.1) but it is not installable
Depends: libmono-cecil-private-cil (>= 2.6.3) but it is not going to be installed
Depends: libmono-codecontracts4.0-cil (>= 1.0) but it is not going to be installed
Depends: libmono-compilerservices-symbolwriter4.0-cil (>= 1.0) but it is not going to be installed
Depends: libmono-corlib2.0-cil (>= 2.6.3) but it is not going to be installed
Depends: libmono-corlib4.0-cil (>= 2.10.1) but it is not going to be installed
Depends: libmono-peapi2.0-cil (>= 2.4.2) but it is not going to be installed
Why does this error occur and how can I fix it?
Also, is it necessary to install mono-devel for a production system? I understand that mono-devel contains various development tools and pulls in the default development stack for Mono .
We may be using mono-devel for C#/ASP.NET webforms compilation and development.
[EDIT June 13 2016 7:46AM] This morning I ran sudo apt-get -f install followed by sudo apt-get remove mono-devel. Here is the resulting error message: vanhuys@udel-ThinkStation-S10:~$ sudo apt-get remove mono-devel
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: libapache2-mod-mono : Depends: mono-apache-server (>= 4.2) but it is not going to be installed or mono-apache-server4 (>= 4.2) but it is not going to be installed Depends: mono-apache-server (< 4.4) but it is not going to be installed or mono-apache-server4 (< 4.4) but it is not going to be installed E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
sudo apt-get update
before a package install ... and before removing a package. I.e. : Currently Ubuntu 16.04 receives updates every day .... will be more consistent in a few months. -apt-get install mono-devel
(and apt is trying to upgrade it to the latest version). I don't see how you could get this error message if you were removingmono-devel
. If this is really the output fromapt-get purge mono-devel
, what doesapt-get -f install
do?/var/log/apt
might provide a clue.