Can't get Manager

After an upgraded of Manager yesterday, I haven’t been able to get Manager to load. Upgraded again today with same result.
Also updated my OS, still Manager will not load

What operating system? What edition (desktop or server)?

Ubuntu 15.1 on Dell System. Have used this OS on all my systems for years with no Manager issues.

I’m not an Ubuntu expert, but I believe you need to update Mono as a minimum. Check out this topic: Updating Manager fails. Also, search the forum for “ubuntu mono” and you will find several more.

I believe that you will find that Ubuntu 15.10 end of life was in July 2016 or thereabouts.
“Standard” releases of Ubuntu are typically supported for 9 months whereas “LTS” releases are supported for 5 years, and whilst it maybe that you can manually update Mono and then update Manager from there on your existing 15.10 installation, IMHO you should first be updating to a currently supported operating system version, as you will then be receiving all of the current security and other updates which not only protects you, but everyone else on the net besides.