See here if your SEL is still on mono 3.2.8 and you are trying to get to mono 5.



SSH ONLY and on Systems with 3.2.8 where original Mono 5 SEL script is not working

Backup your system before making any changes in the Linux OS.

Login with root

cd /etc/apt/lists/sources.d

nano sources.list to find out which version of Lubuntu. It will be repeated toward the end of each source line (usually trusty) then exit

EXAMPLE (oneiric repeats)

cd /etc/apt/lists/sources.list.d

There should be a mono sources list file in here

Nano that file and it should contain something like "deb http://download.mono-project.com/repo/ubuntu VERSION main" (VERSION could be wheezy, trusty, bionic, oneiric or something else)

Make sure VERSION matches what was repeated in the sources.list and add "-stable"

EXAMPLE "deb http://download.mono-project.com/repo/ubuntu trusty-stable main"

Save and Exit

Now run apt-get update and apt-get upgrade.

If upgrade is not working/completing, you can run apt-get dist-upgrade. The overall upgrade should take 5-10 minutes. You will see mono 5.XX in the file names as it unpacks and installs.

Users may have to fix some broken events after as this is a big upgrade.