I tried Install Older Version of Mono but it does not help here is what I run
sudo apt-get purge mono-devel
echo "deb http://download.mono-project.com/repo/debian wheezy/snapshots/4.2.4.4 main" | sudo tee /etc/apt/sources.list.d/mono-xamarin.list
sudo apt-get update
sudo apt-get install -f mono-devel=4.2.4.4-0wheezy1
But when I run the last command I get:
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: libmono-cecil-private-cil (< 4.2.4.5) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Depends: mono-mcs (= 4.2.4.4-0wheezy1) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Depends: mono-gac (= 4.2.4.4-0wheezy1) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Depends: mono-xbuild (= 4.2.4.4-0wheezy1) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Depends: libmono-cil-dev (= 4.2.4.4-0wheezy1) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Depends: libmono-2.0-dev (< 4.2.4.4-0wheezy1.1~) but 5.0.0.100-0xamarin4+raspbian8b1 is to be installed
Recommends: mono-csharp-shell but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
I think it has something to do with then I run sudo apt-update I get the following as the last two lines:
W: GPG error: http://debian.yeasoft.net wheezy InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 40FC0CD26BF18B15
W: Conflicting distribution: http://download.mono-project.com wheezy/snapshots/4.2.4.4 InRelease (expected wheezy/snapshots but got wheezy)
